Proteases with modified pro regions

ABSTRACT

The present invention provides methods and compositions for the production of mature proteases in bacterial host cells. The compositions include modified polynucleotides that encode modified proteases, which have at least one mutation in the pro region; the modified serine proteases encoded by the modified polynucleotides; expression cassettes, DNA constructs, and vectors comprising the modified polynucleotides that encode the modified proteases; and the bacterial host cells transformed with the vectors of the invention. The methods include methods for enhancing the production of mature proteases in bacterial host cells e.g.  Bacillus  sp. host cells. The produced proteases find use in the industrial production of enzymes, suitable for use in various industries, including but not limited to the cleaning, animal feed and textile processing industry.

FIELD OF THE INVENTION

The present invention provides methods and compositions for theproduction of mature proteases in bacterial host cells. The compositionsinclude modified polynucleotides that encode modified proteases, whichhave at least one mutation in the pro region; the modified serineproteases encoded by the modified polynucleotides; expression cassettes,DNA constructs, and vectors comprising the modified polynucleotides thatencode the modified proteases; and the bacterial host cells transformedwith the vectors of the invention. The methods include methods forenhancing the production of mature proteases in bacterial host cellse.g. Bacillus sp. host cells. The produced proteases find use in theindustrial production of enzymes, suitable for use in variousindustries, including but not limited to the cleaning, animal feed andtextile processing industry.

BACKGROUND

Microorganisms, such as the Gram-positive microorganism that are membersof the genus Bacillus, have been used for large-scale industrialfermentation due, in part, to their ability to secrete theirfermentation products into their culture media. Secreted proteins areexported across a cell membrane and a cell wall, and then aresubsequently released into the external media.

Indeed, secretion of heterologous polypeptides is a widely usedtechnique in industry. Typically, cells are transformed with a nucleicacid encoding a heterologous polypeptide of interest to be expressed andsecreted to produce large quantities of desired polypeptides. Expressionand secretion of desired polypeptides has been controlled throughgenetic manipulation of the polynucleotides that encode the desiredproteins. Despite various advances in protein production methods, thereremains a need in the art to provide more efficient methods forextracellular protein secretion with the aim to enhance the productionof enzymes such as proteases, which find use in the use in variousindustries, including but not limited to the cleaning, animal feed andtextile processing industry.

SUMMARY OF THE INVENTION

The present invention provides methods and compositions for theproduction of mature proteases in bacterial host cells. The compositionsinclude modified polynucleotides that encode modified proteases, whichhave at least one mutation in the pro region; the modified serineproteases encoded by the modified polynucleotides; expression cassettes,DNA constructs, and vectors comprising the modified polynucleotides thatencode the modified proteases; and the bacterial host cells transformedwith the vectors of the invention. The methods include methods forenhancing the production of mature proteases in bacterial host cellse.g. Bacillus sp. host cells. The produced proteases find use in theindustrial production of enzymes, suitable for use in variousindustries, including but not limited to the cleaning, animal feed andtextile processing industry.

In one embodiment, the invention provides an isolated modifiedpolynucleotide that encodes a modified protease. The isolated modifiedpolynucleotide comprises a first polynucleotide that encodes a signalpeptide, which is operably linked to a second polynucleotide thatencodes the pro region set forth in SEQ ID NO:7, which comprises acombination of substitutions of at least two amino acids at positionschosen from positions 6, 30 and 32 of the pro region. In turn, thesecond polynucleotide is operably linked to a third polynucleotide thatencodes the mature region of a protease that is at least about 60%identical to the mature protease of SEQ ID NO: 9. Preferably, thesubstitutions enhance the production of the mature protease by aBacillus sp. host e.g. Bacillus subtilis.

In another embodiment, the isolated modified polynucleotide comprises afirst polynucleotide that encodes a signal peptide, which is operablylinked to a second polynucleotide that encodes the pro region set forthin SEQ ID NO:7, which comprises a combination of substitutions of atleast two amino acids at positions chosen from positions 6, 30 and 32 ofthe pro region. In turn, the second polynucleotide is operably linked toa third polynucleotide that encodes the mature region of a wild-type orvariant alkaline serine protease derived from Bacillus clausii orBacillus lentus that is at least about 60% identical to the matureprotease of SEQ ID NO: 9. Preferably, the substitutions enhance theproduction of the mature protease by a Bacillus sp. host e.g. Bacillussubtilis.

In another embodiment, the isolated modified polynucleotide comprises afirst polynucleotide that encodes a signal peptide, which is operablylinked to a second polynucleotide that encodes the pro region set forthin SEQ ID NO:7, which comprises a combination of substitutions of atleast two amino acids at positions chosen from positions 6, 30 and 32 ofthe pro region. In turn, the second polynucleotide is operably linked toa third polynucleotide that encodes the mature region of a proteasechosen from SEQ ID NOS:9, 11, 13, 15, 17, 19, and 21. Preferably, thesubstitutions enhance the production of the mature protease by aBacillus sp. host e.g. Bacillus subtilis.

In another embodiment, the invention provides an isolated modifiedpolynucleotide that encodes a modified protease. The isolated modifiedpolynucleotide comprises a first polynucleotide that encodes a signalpeptide chosen from SEQ ID NOS:3 and 5, which is operably linked to asecond polynucleotide that encodes the pro region set forth in SEQ IDNO:7, which comprises a combination of substitutions of at least twoamino acids at positions chosen from positions 6, 30 and 32 of the proregion. In turn, the second polynucleotide is operably linked to a thirdpolynucleotide that encodes the mature region of a protease that is atleast about 60% identical to the mature protease of SEQ ID NO: 9.Preferably, the substitutions enhance the production of the matureprotease by a Bacillus sp. host e.g. Bacillus subtilis.

In another embodiment, the isolated modified polynucleotide comprises afirst polynucleotide that encodes a signal peptide chosen from SEQ IDNOS:3 and 5, which is operably linked to a second polynucleotide thatencodes the pro region set forth in SEQ ID NO:7, which comprises acombination of substitutions of at least two amino acids at positionschosen from positions 6, 30 and 32 of the pro region. In turn, thesecond polynucleotide is operably linked to a third polynucleotide thatencodes the mature region of a wild-type or variant alkaline serineprotease derived from Bacillus clausii or Bacillus lentus that is atleast about 60% identical to the mature protease of SEQ ID NO: 9.Preferably, the substitutions enhance the production of the matureprotease by a Bacillus sp. host e.g. Bacillus subtilis.

In another embodiment, the isolated modified polynucleotide comprises afirst polynucleotide that encodes a signal peptide chosen from SEQ IDNOS:3 and 5, which is operably linked to a second polynucleotide thatencodes the pro region set forth in SEQ ID NO:7, which comprises acombination of substitutions of at least two amino acids at positionschosen from positions 6, 30 and 32 of the pro region. In turn, thesecond polynucleotide is operably linked to a third polynucleotide thatencodes the mature region of a protease chosen from SEQ ID NOS:9, 11,13, 15, 17, 19, and 21. Preferably, the substitutions enhance theproduction of the mature protease by a Bacillus sp. host e.g. Bacillussubtilis.

In another embodiment, the isolated modified polynucleotide comprises afirst polynucleotide that encodes a signal peptide, which is operablylinked to a second polynucleotide that encodes the pro region set forthin SEQ ID NO:7, which comprises a combination of substitutions of atleast two amino acids chosen from E6X-E30G, E6X-E30S, E6X-A32K,E30X-A32K, E30G-A32X, E30S-A32X and E6G-E30G-A32X. In turn, the secondpolynucleotide is operably linked to a third polynucleotide that encodesthe mature region of a protease that is at least about 60% identical tothe mature protease of SEQ ID NO: 9. Preferably, the substitutionsenhance the production of the mature protease by a Bacillus sp. hoste.g. Bacillus subtilis.

In another embodiment, the isolated modified polynucleotide comprises afirst polynucleotide that encodes a signal peptide, which is operablylinked to a second polynucleotide that encodes the pro region set forthin SEQ ID NO:7, which comprises a combination of substitutions of atleast two amino acids chosen from E6X-E30G, E6X-E30S, E6X-A32K,E30X-A32K, E30G-A32X, E30S-A32X and E6G-E30G-A32X. In turn, the secondpolynucleotide is operably linked to a third polynucleotide that encodesthe mature region of a wild-type or variant alkaline serine proteasederived from Bacillus clausii or Bacillus lentus that is at least about60% identical to the mature protease of SEQ ID NO: 9. Preferably, thesubstitutions enhance the production of the mature protease by aBacillus sp. host e.g. Bacillus subtilis.

In another embodiment, the isolated modified polynucleotide comprises afirst polynucleotide that encodes a signal peptide, which is operablylinked to a second polynucleotide that encodes the pro region set forthin SEQ ID NO:7, which comprises a combination of substitutions of atleast two amino acids chosen from E6X-E30G, E6X-E30S, E6X-A32K,E30X-A32K, E30G-A32X, E30S-A32X and E6G-E30G-A32X. In turn, the secondpolynucleotide is operably linked to a third polynucleotide that encodesthe mature region of a protease chosen from SEQ ID NOS:9, 11, 13, 15,17, 19, and 21. Preferably, the substitutions enhance the production ofthe mature protease by a Bacillus sp. host e.g. Bacillus subtilis.

In another embodiment, the invention provides an isolated modifiedpolynucleotide that encodes a modified protease. The isolated modifiedpolynucleotide comprises a first polynucleotide that encodes a signalpeptide chosen from SEQ ID NOS:3 and 5, which is operably linked to asecond polynucleotide that encodes the pro region set forth in SEQ IDNO:7, which comprises a combination of substitutions of at least twoamino acids chosen from E6X-E30G, E6X-E30S, E6X-A32K, E30X-A32K,E30G-A32X, E30S-A32X and E6G-E30G-A32X. In turn, the secondpolynucleotide is operably linked to a third polynucleotide that encodesthe mature region of a protease that is at least about 60% identical tothe mature protease of SEQ ID NO: 9. Preferably, the substitutionsenhance the production of the mature protease by a Bacillus sp. hoste.g. Bacillus subtilis.

In another embodiment, the isolated modified polynucleotide comprises afirst polynucleotide that encodes a signal peptide chosen from SEQ IDNOS:3 and 5, which is operably linked to a second polynucleotide thatencodes the pro region set forth in SEQ ID NO:7, which comprises acombination of substitutions of at least two amino acids chosen fromE6X-E30G, E6X-E30S, E6X-A32K, E30X-A32K, E30G-A32X, E30S-A32X andE6G-E30G-A32X. In turn, the second polynucleotide is operably linked toa third polynucleotide that encodes the mature region of a wild-type orvariant alkaline serine protease derived from Bacillus clausii orBacillus lentus that is at least about 60% identical to the matureprotease of SEQ ID NO: 9. Preferably, the substitutions enhance theproduction of the mature protease by a Bacillus sp. host e.g. Bacillussubtilis.

In another embodiment, the isolated modified polynucleotide comprises afirst polynucleotide that encodes a signal peptide chosen from SEQ IDNOS:3 and 5, which is operably linked to a second polynucleotide thatencodes the pro region set forth in SEQ ID NO:7, which comprises acombination of substitutions of at least two amino acids chosen fromE6X-E30G, E6X-E30S, E6X-A32K, E30X-A32K, E30G-A32X, E30S-A32X andE6G-E30G-A32X. In turn, the second polynucleotide is operably linked toa third polynucleotide that encodes the mature region of a proteasechosen from SEQ ID NOS:9, 11, 13, 15, 17, 19, and 21. Preferably, thesubstitutions enhance the production of the mature protease by aBacillus sp. host e.g. Bacillus subtilis.

In another embodiment, the isolated modified polynucleotide comprises afirst polynucleotide that encodes a signal peptide, which is operablylinked to a second polynucleotide that encodes the pro region set forthin SEQ ID NO:7, which comprises a combination of substitutions of atleast two amino acids chosen from E6R-A32K, E6N-A32K, E6D-A32K,E6I-A32K, E6K-A32K, E6M-A32K, E6P-A32K, E6S-A32K, E6T-A32K, E6N-A32K,E30W-A32K, E30V-A32K, E6A-E30G, E6R-E30G, E6C-E30G, E6Q-E30G, E6G-E30G,E6H-E30G, E6K-E30G, E6S-E30G, E6W-E30G, E30G-A32R, E30G-A32Q, E30G-A32E,E30G-A32G, E30G-A32H, E30G-A32I, E30G-A32K, E30G-A32S, E30G-A32T,E30G-A32W, E30G-A32V, E6G-E30G-A32E, E6G-E30G-A32S, E6G-E30G-A32T,E6G-E30G-A32W, E6A-E30G, E6R-E30G, E6N-E30G, E6D-E30G, E6C-E30G,E6Q-E30G, E6G-E30G, E6H-E30G, E6K-E30G, E6M-E30G, E6F-E30G, E6P-E30G,E6S-E30G, E6T-E30G, E6W-E30G, E6V-E30G, E6Y-E30G, E6A-E30S, E6G-E30S,E6L-E30S, E6K-E30S, E6F-E30S, E6P-E30S, E6Y-E30S, E6V-E30S, E30S-A32R,E30S-A32N, E30S-A32D, E30S-A32C, E30S-A32Q, E30S-A32E, E30S-A32G,E30S-A32H, E30S-A32L, E30S-A32K, E30S-A32M, E30S-A32F, E30S-A32P,E30S-A32S, E30S-A32T, E30S-A32W, E30S-A32Y, and E30S-A32V. In turn, thesecond polynucleotide is operably linked to a third polynucleotide thatencodes the mature region of a protease that is at least about 60%identical to the mature protease of SEQ ID NO: 9. Preferably, thesubstitutions enhance the production of the mature protease by aBacillus sp. host e.g. Bacillus subtilis.

In another embodiment, the isolated modified polynucleotide comprises afirst polynucleotide that encodes a signal peptide, which is operablylinked to a second polynucleotide that encodes the pro region set forthin SEQ ID NO:7, which comprises a combination of substitutions of atleast two amino acids chosen from E6R-A32K, E6N-A32K, E6D-A32K,E6I-A32K, E6K-A32K, E6M-A32K, E6P-A32K, E6S-A32K, E6T-A32K, E6N-A32K,E30W-A32K, E30V-A32K, E6A-E30G, E6R-E30G, E6C-E30G, E6Q-E30G, E6G-E30G,E6H-E30G, E6K-E30G, E6S-E30G, E6W-E30G, E30G-A32R, E30G-A32Q, E30G-A32E,E30G-A32G, E30G-A32H, E30G-A32I, E30G-A32K, E30G-A32S, E30G-A32T,E30G-A32W, E30G-A32V, E6G-E30G-A32E, E6G-E30G-A32S, E6G-E30G-A32T,E6G-E30G-A32W, E6A-E30G, E6R-E30G, E6N-E30G, E6D-E30G, E6C-E30G,E6Q-E30G, E6G-E30G, E6H-E30G, E6K-E30G, E6M-E30G, E6F-E30G, E6P-E30G,E6S-E30G, E6T-E30G, E6W-E30G, E6V-E30G, E6Y-E30G, E6A-E30S, E6G-E30S,E6L-E30S, E6K-E30S, E6F-E30S, E6P-E30S, E6Y-E30S, E6V-E30S, E30S-A32R,E30S-A32N, E30S-A32D, E30S-A32C, E30S-A32Q, E30S-A32E, E30S-A32G,E30S-A32H, E30S-A32L, E30S-A32K, E30S-A32M, E30S-A32F, E30S-A32P,E30S-A32S, E30S-A32T, E30S-A32W, E30S-A32Y, and E30S-A32V. In turn, thesecond polynucleotide is operably linked to a third polynucleotide thatencodes the mature region of a wild-type or variant alkaline serineprotease derived from Bacillus clausii or Bacillus lentus that is atleast about 60% identical to the mature protease of SEQ ID NO: 9.Preferably, the substitutions enhance the production of the matureprotease by a Bacillus sp. host e.g. Bacillus subtilis.

In another embodiment, the isolated modified polynucleotide comprises afirst polynucleotide that encodes a signal peptide, which is operablylinked to a second polynucleotide that encodes the pro region set forthin SEQ ID NO:7, which comprises a combination of substitutions of atleast two amino acids chosen from E6R-A32K, E6N-A32K, E6D-A32K,E6I-A32K, E6K-A32K, E6M-A32K, E6P-A32K, E6S-A32K, E6T-A32K, E6N-A32K,E30W-A32K, E30V-A32K, E6A-E30G, E6R-E30G, E6C-E30G, E6Q-E30G, E6G-E30G,E6H-E30G, E6K-E30G, E6S-E30G, E6W-E30G, E30G-A32R, E30G-A32Q, E30G-A32E,E30G-A32G, E30G-A32H, E30G-A32I, E30G-A32K, E30G-A32S, E30G-A32T,E30G-A32W, E30G-A32V, E6G-E30G-A32E, E6G-E30G-A32S, E6G-E30G-A32T,E6G-E30G-A32W, E6A-E30G, E6R-E30G, E6N-E30G, E6D-E30G, E6C-E30G,E6Q-E30G, E6G-E30G, E6H-E30G, E6K-E30G, E6M-E30G, E6F-E30G, E6P-E30G,E6S-E30G, E6T-E30G, E6W-E30G, E6V-E30G, E6Y-E30G, E6A-E30S, E6G-E30S,E6L-E30S, E6K-E30S, E6F-E30S, E6P-E30S, E6Y-E30S, E6V-E30S, E30S-A32R,E30S-A32N, E30S-A32D, E30S-A32C, E30S-A32Q, E30S-A32E, E30S-A32G,E30S-A32H, E30S-A32L, E30S-A32K, E30S-A32M, E30S-A32F, E30S-A32P,E30S-A32S, E30S-A32T, E30S-A32W, E30S-A32Y, and E30S-A32V. In turn, thesecond polynucleotide is operably linked to a third polynucleotide thatencodes the mature region of a protease chosen from SEQ ID NOS:9, 11,13, 15, 17, 19, and 21. Preferably, the substitutions enhance theproduction of the mature protease by a Bacillus sp. host e.g. Bacillussubtilis.

In another embodiment, the invention provides an isolated modifiedpolynucleotide that encodes a modified protease. The isolated modifiedpolynucleotide comprises a first polynucleotide that encodes a signalpeptide chosen from SEQ ID NOS:3 and 5, which is operably linked to asecond polynucleotide that encodes the pro region set forth in SEQ IDNO:7, which comprises a combination of substitutions of at least twoamino acids chosen from E6R-A32K, E6N-A32K, E6D-A32K, E6I-A32K,E6K-A32K, E6M-A32K, E6P-A32K, E6S-A32K, E6T-A32K, E6N-A32K, E30W-A32K,E30V-A32K, E6A-E30G, E6R-E30G, E6C-E30G, E6Q-E30G, E6G-E30G, E6H-E30G,E6K-E30G, E6S-E30G, E6W-E30G, E30G-A32R, E30G-A32Q, E30G-A32E,E30G-A32G, E30G-A32H, E30G-A32I, E30G-A32K, E30G-A32S, E30G-A32T,E30G-A32W, E30G-A32V, E6G-E30G-A32E, E6G-E30G-A32S, E6G-E30G-A32T,E6G-E30G-A32W, E6A-E30G, E6R-E30G, E6N-E30G, E6D-E30G, E6C-E30G,E6Q-E30G, E6G-E30G, E6H-E30G, E6K-E30G, E6M-E30G, E6F-E30G, E6P-E30G,E6S-E30G, E6T-E30G, E6W-E30G, E6V-E30G, E6Y-E30G, E6A-E30S, E6G-E30S,E6L-E30S, E6K-E30S, E6F-E30S, E6P-E30S, E6Y-E30S, E6V-E30S, E30S-A32R,E30S-A32N, E30S-A32D, E30S-A32C, E30S-A32Q, E30S-A32E, E30S-A32G,E30S-A32H, E30S-A32L, E30S-A32K, E30S-A32M, E30S-A32F, E30S-A32P,E30S-A32S, E30S-A32T, E30S-A32W, E30S-A32Y, and E30S-A32V. In turn, thesecond polynucleotide is operably linked to a third polynucleotide thatencodes the mature region of a protease that is at least about 60%identical to the mature protease of SEQ ID NO: 9. Preferably, thesubstitutions enhance the production of the mature protease by aBacillus sp. host e.g. Bacillus subtilis.

In another embodiment, the isolated modified polynucleotide comprises afirst polynucleotide that encodes a signal peptide chosen from SEQ IDNOS:3 and 5, which is operably linked to a second polynucleotide thatencodes the pro region set forth in SEQ ID NO:7, which comprises acombination of substitutions of at least two amino acids chosen fromE6R-A32K, E6N-A32K, E6D-A32K, E6I-A32K, E6K-A32K, E6M-A32K, E6P-A32K,E6S-A32K, E6T-A32K, E6N-A32K, E30W-A32K, E30V-A32K, E6A-E30G, E6R-E30G,E6C-E30G, E6Q-E30G, E6G-E30G, E6H-E30G, E6K-E30G, E6S-E30G, E6W-E30G,E30G-A32R, E30G-A32Q, E30G-A32E, E30G-A32G, E30G-A32H, E30G-A32I,E30G-A32K, E30G-A32S, E30G-A32T, E30G-A32W, E30G-A32V, E6G-E30G-A32E,E6G-E30G-A32S, E6G-E30G-A32T, E6G-E30G-A32W, E6A-E30G, E6R-E30G,E6N-E30G, E6D-E30G, E6C-E30G, E6Q-E30G, E6G-E30G, E6H-E30G, E6K-E30G,E6M-E30G, E6F-E30G, E6P-E30G, E6S-E30G, E6T-E30G, E6W-E30G, E6V-E30G,E6Y-E30G, E6A-E30S, E6G-E30S, E6L-E30S, E6K-E30S, E6F-E30S, E6P-E30S,E6Y-E30S, E6V-E30S, E30S-A32R, E30S-A32N, E30S-A32D, E30S-A32C,E30S-A32Q, E30S-A32E, E30S-A32G, E30S-A32H, E30S-A32L, E30S-A32K,E30S-A32M, E30S-A32F, E30S-A32P, E30S-A32S, E30S-A32T, E30S-A32W,E30S-A32Y, and E30S-A32V. In turn, the second polynucleotide is operablylinked to a third polynucleotide that encodes the mature region of awild-type or variant alkaline serine protease derived from Bacillusclausii or Bacillus lentus that is at least about 60% identical to themature protease of SEQ ID NO: 9. Preferably, the substitutions enhancethe production of the mature protease by a Bacillus sp. host e.g.Bacillus subtilis.

In another embodiment, the isolated modified polynucleotide comprises afirst polynucleotide that encodes a signal peptide chosen from SEQ IDNOS:3 and 5, which is operably linked to a second polynucleotide thatencodes the pro region set forth in SEQ ID NO:7, which comprises acombination of substitutions of at least two amino acids chosen fromE6R-A32K, E6N-A32K, E6D-A32K, E6I-A32K, E6K-A32K, E6M-A32K, E6P-A32K,E6S-A32K, E6T-A32K, E6N-A32K, E30W-A32K, E30V-A32K, E6A-E30G, E6R-E30G,E6C-E30G, E6Q-E30G, E6G-E30G, E6H-E30G, E6K-E30G, E6S-E30G, E6W-E30G,E30G-A32R, E30G-A32Q, E30G-A32E, E30G-A32G, E30G-A32H, E30G-A32I,E30G-A32K, E30G-A32S, E30G-A32T, E30G-A32W, E30G-A32V, E6G-E30G-A32E,E6G-E30G-A32S, E6G-E30G-A32T, E6G-E30G-A32W, E6A-E30G, E6R-E30G,E6N-E30G, E6D-E30G, E6C-E30G, E6Q-E30G, E6G-E30G, E6H-E30G, E6K-E30G,E6M-E30G, E6F-E30G, E6P-E30G, E6S-E30G, E6T-E30G, E6W-E30G, E6V-E30G,E6Y-E30G, E6A-E30S, E6G-E30S, E6L-E30S, E6K-E30S, E6F-E30S, E6P-E30S,E6Y-E30S, E6V-E30S, E30S-A32R, E30S-A32N, E30S-A32D, E30S-A32C,E30S-A32Q, E30S-A32E, E30S-A32G, E30S-A32H, E30S-A32L, E30S-A32K,E30S-A32M, E30S-A32F, E30S-A32P, E30S-A32S, E30S-A32T, E30S-A32W,E30S-A32Y, and E30S-A32V. In turn, the second polynucleotide is operablylinked to a third polynucleotide that encodes the mature region of awild-type or variant alkaline serine protease derived from Bacillusclausii or Bacillus lentus that is at least about 60% identical to themature protease of SEQ ID NO: 9. Preferably, the substitutions enhancethe production of the mature protease by a Bacillus sp. host e.g.Bacillus subtilis.

In another embodiment, the invention provides an expression vectorcomprising an isolated modified polynucleotide, which comprises a firstpolynucleotide that encodes a signal peptide, which is operably linkedto a second polynucleotide that encodes the pro region set forth in SEQID NO:7 that comprises a combination of substitutions of at least twoamino acids at positions chosen from positions 6, 30 and 32 of the proregion. In turn, the second polynucleotide is operably linked to a thirdpolynucleotide that encodes the mature region of a protease that is atleast about 60% identical to the mature protease of SEQ ID NO: 9.Preferably, the mature protease is a wild-type or variant alkalineserine protease derived from Bacillus clausii or Bacillus lentus e.g.SEQ ID NOS:9, 11, 13, 15, 17, 19, and 21. In some embodiments, theexpression of the isolated polynucleotide is driven by the AprE promotercomprised in the expression vector.

In another embodiment, the expression vector comprises an isolatedmodified polynucleotide, which comprises a first polynucleotide thatencodes a signal peptide chosen from SEQ ID NOS:3 and 5, which isoperably linked to a second polynucleotide that encodes the pro regionset forth in SEQ ID NO:7 that comprises a combination of substitutionsof at least two amino acids at positions chosen from positions 6, 30 and32 of the pro region. In turn, the second polynucleotide is operablylinked to a third polynucleotide that encodes the mature region of aprotease that is at least about 60% identical to the mature protease ofSEQ ID NO: 9. Preferably, the mature protease is a wild-type or variantalkaline serine protease derived from Bacillus clausii or Bacilluslentus e.g. SEQ ID NOS:9, 11, 13, 15, 17, 19, and 21. In someembodiments, the expression of the isolated polynucleotide is driven bythe AprE promoter comprised in the expression vector.

In another embodiment, the invention provides an expression vectorcomprising an isolated modified polynucleotide, which comprises a firstpolynucleotide that encodes a signal peptide, which is operably linkedto a second polynucleotide that encodes the pro region set forth in SEQID NO:7 that comprises a combination of substitutions of at least twoamino acids chosen from E6X-E30G, E6X-E30S, E6X-A32K, E30X-A32K,E30G-A32X, E30S-A32X and E6G-E30G-A32X. In turn, the secondpolynucleotide is operably linked to a third polynucleotide that encodesthe mature region of a protease that is at least about 60% identical tothe mature protease of SEQ ID NO: 9. Preferably, the mature protease isa wild-type or variant alkaline serine protease derived from Bacillusclausii or Bacillus lentus e.g. SEQ ID NOS:9, 11, 13, 15, 17, 19, and21. In some embodiments, the expression of the isolated polynucleotideis driven by the AprE promoter comprised in the expression vector.

In another embodiment, the expression vector comprises an isolatedmodified polynucleotide, which comprises a first polynucleotide thatencodes a signal peptide chosen from SEQ ID NOS:3 and 5, which isoperably linked to a second polynucleotide that encodes the pro regionset forth in SEQ ID NO:7 that comprises a combination of substitutionsof at least two amino acids chosen from E6X-E30G, E6X-E30S, E6X-A32K,E30X-A32K, E30G-A32X, E30S-A32X and E6G-E30G-A32X. In turn, the secondpolynucleotide is operably linked to a third polynucleotide that encodesthe mature region of a protease that is at least about 60% identical tothe mature protease of SEQ ID NO: 9. Preferably, the mature protease isa wild-type or variant alkaline serine protease derived from Bacillusclausii or Bacillus lentus e.g. SEQ ID NOS:9, 11, 13, 15, 17, 19, and21. In some embodiments, the expression of the isolated polynucleotideis driven by the AprE promoter comprised in the expression vector.

In another embodiment, the invention provides an expression vectorcomprising an isolated modified polynucleotide, which comprises a firstpolynucleotide that encodes a signal peptide, which is operably linkedto a second polynucleotide that encodes the pro region set forth in SEQID NO:7 that comprises a combination of substitutions of at least twoamino acids chosen from E6R-A32K, E6N-A32K, E6D-A32K, E6I-A32K,E6K-A32K, E6M-A32K, E6P-A32K, E6S-A32K, E6T-A32K, E6N-A32K, E30W-A32K,E30V-A32K, E6A-E30G, E6R-E30G, E6C-E30G, E6Q-E30G, E6G-E30G, E6H-E30G,E6K-E30G, E6S-E30G, E6W-E30G, E30G-A32R, E30G-A32Q, E30G-A32E,E30G-A32G, E30G-A32H, E30G-A32I, E30G-A32K, E30G-A32S, E30G-A32T,E30G-A32W, E30G-A32V, E6G-E30G-A32E, E6G-E30G-A32S, E6G-E30G-A32T,E6G-E30G-A32W, E6A-E30G, E6R-E30G, E6N-E30G, E6D-E30G, E6C-E30G,E6Q-E30G, E6G-E30G, E6H-E30G, E6K-E30G, E6M-E30G, E6F-E30G, E6P-E30G,E6S-E30G, E6T-E30G, E6W-E30G, E6V-E30G, E6Y-E30G, E6A-E30S, E6G-E30S,E6L-E30S, E6K-E30S, E6F-E30S, E6P-E30S, E6Y-E30S, E6V-E30S, E30S-A32R,E30S-A32N, E30S-A32D, E30S-A32C, E30S-A32Q, E30S-A32E, E30S-A32G,E30S-A32H, E30S-A32L, E30S-A32K, E30S-A32M, E30S-A32F, E30S-A32P,E30S-A32S, E30S-A32T, E30S-A32W, E30S-A32Y, and E30S-A32V. In turn, thesecond polynucleotide is operably linked to a third polynucleotide thatencodes the mature region of a protease that is at least about 60%identical to the mature protease of SEQ ID NO: 9. Preferably, the matureprotease is a wild-type or variant alkaline serine protease derived fromBacillus clausii or Bacillus lentus e.g. SEQ ID NOS:9, 11, 13, 15, 17,19, and 21. In some embodiments, the expression of the isolatedpolynucleotide is driven by the AprE promoter comprised in theexpression vector.

In another embodiment, the expression vector comprises an isolatedmodified polynucleotide, which comprises a first polynucleotide thatencodes a signal peptide chosen from SEQ ID NOS:3 and 5, which isoperably linked to a second polynucleotide that encodes the pro regionset forth in SEQ ID NO:7 that comprises a combination of substitutionsof at least two amino acids chosen from E6R-A32K, E6N-A32K, E6D-A32K,E6I-A32K, E6K-A32K, E6M-A32K, E6P-A32K, E6S-A32K, E6T-A32K, E6N-A32K,E30W-A32K, E30V-A32K, E6A-E30G, E6R-E30G, E6C-E30G, E6Q-E30G, E6G-E30G,E6H-E30G, E6K-E30G, E6S-E30G, E6W-E30G, E30G-A32R, E30G-A32Q, E30G-A32E,E30G-A32G, E30G-A32H, E30G-A32I, E30G-A32K, E30G-A32S, E30G-A32T,E30G-A32W, E30G-A32V, E6G-E30G-A32E, E6G-E30G-A32S, E6G-E30G-A32T,E6G-E30G-A32W, E6A-E30G, E6R-E30G, E6N-E30G, E6D-E30G, E6C-E30G,E6Q-E30G, E6G-E30G, E6H-E30G, E6K-E30G, E6M-E30G, E6F-E30G, E6P-E30G,E6S-E30G, E6T-E30G, E6W-E30G, E6V-E30G, E6Y-E30G, E6A-E30S, E6G-E30S,E6L-E30S, E6K-E30S, E6F-E30S, E6P-E30S, E6Y-E30S, E6V-E30S, E30S-A32R,E30S-A32N, E30S-A32D, E30S-A32C, E30S-A32Q, E30S-A32E, E30S-A32G,E30S-A32H, E30S-A32L, E30S-A32K, E30S-A32M, E30S-A32F, E30S-A32P,E30S-A32S, E30S-A32T, E30S-A32W, E30S-A32Y, and E30S-A32V. In turn, thesecond polynucleotide is operably linked to a third polynucleotide thatencodes the mature region of a protease that is at least about 60%identical to the mature protease of SEQ ID NO: 9. Preferably, the matureprotease is a wild-type or variant alkaline serine protease derived fromBacillus clausii or Bacillus lentus e.g. SEQ ID NOS:9, 11, 13, 15, 17,19, and 21. In some embodiments, the expression of the isolatedpolynucleotide is driven by the AprE promoter comprised in theexpression vector.

In another embodiment, the invention provides a Bacillus sp. host celle.g. Bacillus subtilis, which comprises any one of the expressionvectors described above. Preferably, the substitutions comprised in thepro region of the modified polynucleotide enhance the production of themature protease from the Bacillus host cell. In addition to Bacillussubtilis, other host cells that can be used to express the modifiedpolynucleotides from the expression vectors include Bacilluslicheniformis, Bacillus lentus, Bacillus brevis, Bacillusstearothermophilus, Bacillus alkalophilus, Bacillus amyloliquefaciens,Bacillus clausii, Bacillus halodurans, Bacillus megaterium, Bacilluscoagulans, Bacillus circulans, Bacillus lautus, and Bacillusthuringiensis.

In another embodiment, the invention provides a method for producing amature protease in a Bacillus sp. host cell. The method includesproviding any one of the expression vectors described above,transforming the expression vector into a Bacillus sp. host cell, andculturing the transformed host cell under suitable conditions to producethe protease. Preferably, the host cell is a Bacillus subtilis hostcell. However, in addition to Bacillus subtilis, other host cells thatcan be used to produce the mature proteases from the expression vectorinclude Bacillus licheniformis, Bacillus lentus, Bacillus brevis,Bacillus stearothermophilus, Bacillus alkalophilus, Bacillusamyloliquefaciens, Bacillus clausii, Bacillus halodurans, Bacillusmegaterium, Bacillus coagulans, Bacillus circulans, Bacillus lautus, andBacillus thuringiensis.

In another embodiment, the method produces the mature protease of SEQ IDNO:9 by providing an expression vector that expresses an isolatedmodified polynucleotide comprising a first polynucleotide encoding thesignal peptide of SEQ ID NO:3, a second polynucleotide encoding the proregion of SEQ ID NO:7 that includes a combination of substitutionschosen from E6R-A32K, E6N-A32K, E6D-A32K, E6I-A32K, E6K-A32K, E6M-A32K,E6P-A32K, E6S-A32K, E6T-A32K, E6N-A32K, E30W-A32K, E30V-A32K, and thethird polynucleotide, which encodes the mature protease of SEQ ID NO:9.The expression vector is transformed into a Bacillus sp. host cell e.g.Bacillus subtilis, which is grown under suitable conditions to producethe mature protease.

In another embodiment, the method produces the mature protease of SEQ IDNO:17 by providing an expression vector that expresses an isolatedmodified polynucleotide comprising a first polynucleotide encoding thesignal peptide of SEQ ID NO:3, a second polynucleotide encoding the proregion of SEQ ID NO:7 that includes a combination of substitutionschosen from E6A-E30G, E6R-E30G, E6C-E30G, E6Q-E30G, E6G-E30G, E6H-E30G,E6K-E30G, E6S-E30G, E6W-E30G, E30G-A32R, E30G-A32Q, E30G-A32E,E30G-A32G, E30G-A32H, E30G-A32I, E30G-A32K, E30G-A32S, E30G-A32T,E30G-A32W, E30G-A32V, E6G-E30G-A32E, E6G-E30G-A32S, E6G-E30G-A32T, andE6G-E30G-A32W, and the third polynucleotide, which encodes the matureprotease of SEQ ID NO:17. The expression vector is transformed into aBacillus sp. host cell e.g. Bacillus subtilis, which is grown undersuitable conditions to produce the mature protease.

In another embodiment, the method produces the mature protease of SEQ IDNO:19 by providing an expression vector that expresses an isolatedmodified polynucleotide comprising a first polynucleotide encoding thesignal peptide of SEQ ID NO:3, a second polynucleotide encoding the proregion of SEQ ID NO:7 that includes a combination of substitutionschosen from E6A-E30G, E6R-E30G, E6N-E30G, E6D-E30G, E6C-E30G, E6Q-E30G,E6G-E30G, E6H-E30G, E6K-E30G, E6M-E30G, E6F-E30G, E6P-E30G, E6S-E30G,E6T-E30G, E6W-E30G, E6V-E30G, and E6Y-E30G, and the thirdpolynucleotide, which encodes the mature protease of SEQ ID NO:19. Theexpression vector is transformed into a Bacillus sp. host cell e.g.Bacillus subtilis, which is grown under suitable conditions to producethe mature protease.

In another embodiment, the method produces the mature protease of SEQ IDNO:21 by providing an expression vector that expresses an isolatedmodified polynucleotide comprising a first polynucleotide encoding thesignal peptide of SEQ ID NO:3, a second polynucleotide encoding the proregion of SEQ ID NO:7 that includes a combination of substitutionschosen from E6A-E30S, E6G-E30S, E6L-E30S, E6K-E30S, E6F-E30S, E6P-E30S,E6Y-E30S, E6V-E30S, E30S-A32R, E30S-A32N, E30S-A32D, E30S-A32C,E30S-A32Q, E30S-A32E, E30S-A32G, E30S-A32H, E30S-A32L, E30S-A32K,E30S-A32M, E30S-A32F, E30S-A32P, E30S-A32S, E30S-A32T, E30S-A32W,E30S-A32Y, and E30S-A32V, and the third polynucleotide, which encodesthe mature protease of SEQ ID NO:21. The expression vector istransformed into a Bacillus sp. host cell e.g. Bacillus subtilis, whichis grown under suitable conditions to produce the mature protease.

In other embodiments, the isolated modified polynucleotides comprise oneamino acid substitution, which preferably enhances the production of amature protease from a Bacillus sp. host cell. In one embodiment, theisolated modified polynucleotide comprises a first polynucleotideencoding the signal peptide of SEQ ID NO:3, and that is operably linkedto a second polynucleotide that encodes the pro region set forth in SEQID NO:7, which comprises the substitution of an amino acid chosen fromE6A, E6R, E6C, E6Q, E6H, E6I, E6K, E6M, E6S, E6Y, E30A, E30R, E30N,E30D, E30Q, E30G, E30L, E30M, E30P, E30S, E30T, E30W, E30Y, E30V, A32,A32R, A32C, A32E, A32G, A32L, A32K, A32F, A32T, A32Y, and A32V. Thesecond polynucleotide is operably linked to a third polynucleotide thatencodes the mature region of the protease of SEQ ID NO:17.

In another embodiment, the isolated modified polynucleotide comprises afirst polynucleotide encoding the signal peptide of SEQ ID NO:3, andthat is operably linked to a second polynucleotide that encodes the proregion set forth in SEQ ID NO:7, which comprises the substitution of anamino acid chosen from E6A, E6R, E6N, E6C, E6Q, E6G, E6H, E6M, E6F, E6P,E6S, E6T, E6W, E6V, A32K, A32T, and A32V. The second polynucleotide isoperably linked to a third polynucleotide that encodes the mature regionof the protease of SEQ ID NO:9.

In another embodiment, the isolated modified polynucleotide comprises afirst polynucleotide encoding the signal peptide of SEQ ID NO:3, andthat is operably linked to a second polynucleotide that encodes the proregion set forth in SEQ ID NO:7, which comprises the substitution of anamino acid chosen from E6A, E6H, E6K, and E6R, E30A, E30R, E30N, E30D,E30G, E30H, E30L, E30K, E30F, E30S, E30T, and E30V. The secondpolynucleotide is operably linked to a third polynucleotide that encodesthe mature region of the protease of SEQ ID NO:19.

In another embodiment, the isolated modified polynucleotide comprises afirst polynucleotide encoding the signal peptide of SEQ ID NO:3, andthat is operably linked to a second polynucleotide that encodes the proregion set forth in SEQ ID NO:7, which comprises the substitution of anamino acid chosen from E6A, E6R, E6Q, E6G, E6L, E6K, E6M, E6F, E6T, E6V,E30R, E30Q, E30G, E30I, E30L, E30M, E30F, E30P, E30T, E30W, E30Y, E30V,A32Q, A32S, A32T, and A32V. The second polynucleotide is operably linkedto a third polynucleotide that encodes the mature region of the proteaseof SEQ ID NO:11.

In another embodiment, the isolated modified polynucleotide comprises afirst polynucleotide encoding the signal peptide of SEQ ID NO:3, andthat is operably linked to a second polynucleotide that encodes the proregion set forth in SEQ ID NO:7, which comprises the substitution of anamino acid chosen from E30A, E30R, E30N, E30D, E30C, E30G, E30H, E30M,E30F, E30S, E30W, A32L, A32F, and A32V. The second polynucleotide isoperably linked to a third polynucleotide that encodes the mature regionof the protease of SEQ ID NO:21.

The method for producing the mature proteases expressed from modifiedpolynucleotides comprising two or three substitutions in the pro regionis also used for producing mature proteases expressed from modifiedpolynucleotides comprising single amino acid substitutions.

In one embodiment, the method includes providing any one of theexpression vectors described above and containing a modifiedpolynucleotide comprising a single amino acid substitution in the proregion, transforming the expression vector into a Bacillus sp. hostcell, and culturing the transformed host cell under suitable conditionsto produce the protease. Preferably, the host cell is a Bacillussubtilis host cell. However, in addition to Bacillus subtilis, otherhost cells that can be used to produce the mature proteases from theexpression vector include Bacillus licheniformis, Bacillus lentus,Bacillus brevis, Bacillus stearothermophilus, Bacillus alkalophilus,Bacillus amyloliquefaciens, Bacillus clausii, Bacillus halodurans,Bacillus megaterium, Bacillus coagulans, Bacillus circulans, Bacilluslautus, and Bacillus thuringiensis.

In one embodiment, the method produces the mature protease of SEQ IDNO:17 by providing an expression vector that expresses an isolatedmodified polynucleotide comprising a first polynucleotide encoding thesignal peptide of SEQ ID NO:3, a second polynucleotide encoding the proregion of SEQ ID NO:7 that includes a single amino acid substitutionchosen from E6A, E6R, E6C, E6Q, E6H, E6I, E6K, E6M, E6S, E6Y, E30A,E30R, E30N, E30D, E30Q, E30G, E30L, E30M, E30P, E30S, E30T, E30W, E30Y,E30V, A32, A32R, A32C, A32E, A32G, A32L, A32K, A32F, A32T, A32Y, andA32V, and the third polynucleotide, which encodes the mature protease ofSEQ ID NO:17. The expression vector is transformed into a Bacillus sp.host cell e.g. Bacillus subtilis, which is grown under suitableconditions to produce the mature protease.

In another embodiment, the method produces the mature protease of SEQ IDNO:9 by providing an expression vector that expresses an isolatedmodified polynucleotide comprising a first polynucleotide encoding thesignal peptide of SEQ ID NO:3, a second polynucleotide encoding the proregion of SEQ ID NO:7 that includes a single amino acid substitutionchosen from E6A, E6R, E6N, E6C, E6Q, E6G, E6H, E6M, E6F, E6P, E6S, E6T,E6W, E6V, A32K, A32T, and A32V, and the third polynucleotide, whichencodes the mature protease of SEQ ID NO:9. The expression vector istransformed into a Bacillus sp. host cell e.g. Bacillus subtilis, whichis grown under suitable conditions to produce the mature protease.

In another embodiment, the method produces the mature protease of SEQ IDNO:19 by providing an expression vector that expresses an isolatedmodified polynucleotide comprising a first polynucleotide encoding thesignal peptide of SEQ ID NO:3, a second polynucleotide encoding the proregion of SEQ ID NO:7 that includes a single amino acid substitutionchosen from E6A, E6H, E6K, and E6R, E30A, E30R, E30N, E30D, E30G, E30H,E30L, E30K, E30F, E30S, E30T, and E30V, and the third polynucleotide,which encodes the mature protease of SEQ ID NO:19. The expression vectoris transformed into a Bacillus sp. host cell e.g. Bacillus subtilis,which is grown under suitable conditions to produce the mature protease.

In another embodiment, the method produces the mature protease of SEQ IDNO:11 by providing an expression vector that expresses an isolatedmodified polynucleotide comprising a first polynucleotide encoding thesignal peptide of SEQ ID NO:3, a second polynucleotide encoding the proregion of SEQ ID NO:7 that includes a single amino acid substitutionchosen from E6A, E6R, E6Q, E6G, E6L, E6K, E6M, E6F, E6T, E6V, E30R,E30Q, E30G, E30I, E30L, E30M, E30F, E30P, E30T, E30W, E30Y, E30V, A32Q,A32S, A32T, and A32V, and the third polynucleotide, which encodes themature protease of SEQ ID NO:11. The expression vector is transformedinto a Bacillus sp. host cell e.g. Bacillus subtilis, which is grownunder suitable conditions to produce the mature protease.

In another embodiment, the method produces the mature protease of SEQ IDNO:21 by providing an expression vector that expresses an isolatedmodified polynucleotide comprising a first polynucleotide encoding thesignal peptide of SEQ ID NO:3, a second polynucleotide encoding the proregion of SEQ ID NO:7 that includes a single amino acid substitutionchosen from E30A, E30R, E30N, E30D, E30C, E30G, E30H, E30M, E30F, E30S,E30W, A32L, A32F, and A32V, and the third polynucleotide, which encodesthe mature protease of SEQ ID NO:21. The expression vector istransformed into a Bacillus sp. host cell e.g. Bacillus subtilis, whichis grown under suitable conditions to produce the mature protease.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an alignment of the amino acid sequences of the matureregion of B. lentus wild-type serine protease of SEQ ID NO:9 (GG36), theB. lentus variant serine protease of SEQ ID NO:11, the B. clausii serineprotease of SEQ ID NO:13, and the B. clausii variant serine proteases ofSEQ ID NO:15, SEQ ID NO:17, SEQ ID NO:19, SEQ ID NO:21, SEQ ID NO:23 andSEQ ID NO:25.

FIG. 2 shows an alignment of the amino acid sequence of the unmodifiedpro region of SEQ ID NO:7 with that of unmodified pro regions ofproteases from various Bacillus sp. resulting from a Blast search.

FIGS. 3A and 3B show an alignment of the amino acid sequence of themature protease (SEQ ID NO:9) with that of mature regions of proteasesfrom various Bacillus sp. resulting from a Blast search.

FIG. 4 provides the map of the pJH-Pn plasmid (A) and the map of thepBN3-Pn (B) vector comprising the aprE signal sequence (SEQ ID NO:3),the pro sequence of SEQ ID NO:7 and the polynucleotide encoding themature serine protease Pn.

FIGS. 5A and 5B show an alignment of exemplary polynucleotides (SEQ IDNOS:8, 10, 12, 14, 16, 18, 20, 22, and 24) that encode the matureproteases of SEQ ID NOS:9, 11, 13, 15, 17, 19, 21, 23, and 25,respectively. It is understood that a polypeptide may be coded for bymore than one nucleotide sequence due to the degeneracy of the geneticcode.

DESCRIPTION OF THE INVENTION

This invention provides modified polynucleotides encoding modifiedproteases, and methods for enhancing the production of proteases inmicroorganisms. In particular, the modified polynucleotides comprise oneor more mutations that encode proteases having modifications e.g. aminoacid substitutions, of the pro region to enhance the production of theactive enzyme. The present invention further relates to methods foraltering the expression of proteases in microorganisms, such as Bacillusspecies.

Unless defined otherwise herein, all technical and scientific terms usedherein have the same meaning as commonly understood by one of ordinaryskill in the art to which this invention pertains (e.g. Singleton andSainsbury, Dictionary of Microbiology and Molecular Biology, 2d Ed.,John Wiley and Sons, NY [1994]; and Hale and Markham, The Harper CollinsDictionary of Biology, Harper Perennial, NY [1991]). Although anymethods and materials similar or equivalent to those described hereinfind use in the practice of the present invention, the preferred methodsand materials are described herein. Accordingly, the terms definedimmediately below are more fully described by reference to theSpecification as a whole. Also, as used herein, the singular “a”, “an”and “the” includes the plural reference unless the context clearlyindicates otherwise. Numeric ranges are inclusive of the numbersdefining the range. Unless otherwise indicated, nucleic acids arewritten left to right in 5′ to 3′ orientation; amino acid sequences arewritten left to right in amino to carboxy orientation, respectively. Itis to be understood that this invention is not limited to the particularmethodology, protocols, and reagents described, as these may vary,depending upon the context they are used by those of skill in the art.

It is intended that every maximum numerical limitation given throughoutthis specification include every lower numerical limitation, as if suchlower numerical limitations were expressly written herein. Every minimumnumerical limitation given throughout this specification will includeevery higher numerical limitation, as if such higher numericallimitations were expressly written herein. Every numerical range giventhroughout this specification will include every narrower numericalrange that falls within such broader numerical range, as if suchnarrower numerical ranges were all expressly written herein.

All patents, patent applications, articles and publications mentionedherein, both supra and infra, are hereby expressly incorporated hereinby reference.

Furthermore, the headings provided herein are not limitations of thevarious aspects or embodiments of the invention which can be had byreference to the specification as a whole. Accordingly, the termsdefined immediately below are more fully defined by reference to thespecification as a whole. Nonetheless, in order to facilitateunderstanding of the invention, a number of terms are defined below.

Definitions

As used herein, the terms “isolated” and “purified” refer to a nucleicacid or amino acid (or other component) that is removed from at leastone component with which it is naturally associated.

The term “modified polynucleotide” herein refers to a polynucleotidesequence that has been altered to contain at least one mutation toencode a “modified” protein.

As used herein, the terms “protease” and “proteolytic activity” refer toa protein or peptide exhibiting the ability to hydrolyze peptides orsubstrates having peptide linkages. Many well known procedures exist formeasuring proteolytic activity (Kalisz, “Microbial Proteinases,” In:Fiechter (ed.), Advances in Biochemical Engineering/Biotechnology,[1988]). For example, proteolytic activity may be ascertained bycomparative assays which analyze the produced protease's ability tohydrolyze a commercial substrate. Exemplary substrates useful in suchanalysis of protease or proteolytic activity, include, but are notlimited to di-methyl casein (Sigma C-9801), bovine collagen (SigmaC-9879), bovine elastin (Sigma E-1625), and bovine keratin (ICNBiomedical 902111). Colorimetric assays utilizing these substrates arewell known in the art (See e.g., WO 99/34011; and U.S. Pat. No.6,376,450, both of which are incorporated herein by reference. The AAPFassay (See e.g., Del Mar et al., Anal. Biochem., 99:316-320 [1979]) alsofinds use in determining the production of mature protease. This assaymeasures the rate at which p-nitroaniline is released as the enzymehydrolyzes the soluble synthetic substrate,succinyl-alanine-alanine-proline-phenylalanine-p-nitroanilide(sAAPF-pNA). The rate of production of yellow color from the hydrolysisreaction is measured at 410 nm on a spectrophotometer and isproportional to the active enzyme concentration. In particular, the term“protease” herein refers to a “serine protease”.

As used herein, the terms “subtilisin” and “serine protease” refer anymember of the S8 serine protease family as described in MEROPS—ThePeptidase Data base (Rawlings et al., MEROPS: the peptidase database,Nucleic Acids Res, 34 Database issue, D270-272, 2006, at the websitemerops.sanger.ac.uk/cgi-bin/merops.cgi?id=s08;action=.). The followinginformation was derived from MEROPS—The Peptidase Data base as of Nov.6, 2008 “Peptidase family S8 contains the serine endopeptidase serineprotease and its homologues (Biochem J, 290:205-218, 1993). Family S8,also known as the subtilase family, is the second largest family ofserine peptidases, and can be divided into two subfamilies, withsubtilisin (S08.001) the type-example for subfamily S8A and kexin(S08.070) the type-example for subfamily S8B. Tripeptidyl-peptidase II(TPP-II; S08.090) was formerly considered to be the type-example of athird subfamily, but has since been determined to be misclassified.

The term “parent protease” herein refers to a full-length proteasecomprising pre, pro and mature regions that are naturally expressed incombination. In some embodiments, the pre and/or pro and/or matureregions of a parent protease serve to originate the pre and/or proand/or mature regions of a precursor protease.

The term “precursor protease” herein refers to an unmodified full-lengthprotease comprising a signal peptide, a pro region and a mature region.The precursor protease can be derived from naturally-occurring i.e.wild-type proteases, or from variant proteases. It is the pro region ofa precursor protease that is modified to generate a modified protease.In some embodiments, the precursor protease comprises a pro region and amature region that are derived from one parent protease. In otherembodiments, the precursor protease is a chimeric protein that comprisesa pro region that is derived from one parent protease and a matureregion that is derived from a different parent protease.

The term “chimeric” or “fusion” when used in reference to a protein,herein refer to a protein created through the joining of two or morepolynucleotides which originally coded for separate proteins.Translation of this fusion polynucleotide results in a single chimericpolynucleotide with functional properties derived from each of theoriginal proteins. Recombinant fusion proteins are created artificiallyby recombinant DNA technology. A “chimeric polypeptide,” or “chimera”means a protein containing sequences from more than one polypeptide. Amodified protease can be chimeric in the sense that it contains aportion, region, or domain from one protease fused to one or moreportions, regions, or domains from one or more other protease. By way ofexample, a chimeric protease might comprise the mature region of oneprotease linked to the pro peptide of another protease. The skilledartisan will appreciate that chimeric polypeptides and proteases neednot consist of actual fusions of the protein sequences, but rather,polynucleotides with the corresponding encoding sequences can also beused to express chimeric polypeptides or proteases.

“Naturally-occurring” or “wild-type” herein refer to a protease, or apolynucleotide encoding a protease having the unmodified amino acidsequence identical to that found in nature. Naturally occurring enzymesinclude native enzymes, those enzymes naturally expressed or found inthe particular microorganism. A sequence that is wild-type ornaturally-occurring refers to a sequence from which a variant isderived. The wild-type sequence may encode either a homologous orheterologous protein.

As used herein, “variant” refers to a mature protein which differs fromits corresponding wild-type mature protein by the addition of one ormore amino acids to either or both the C- and N-terminal end,substitution of one or more amino acids at one or a number of differentsites in the amino acid sequence, deletion of one or more amino acids ateither or both ends of the protein or at one or more sites in the aminoacid sequence, and/or insertion of one or more amino acids at one ormore sites in the amino acid sequence of the mature protein. Variantproteins encompass naturally-occurring variants and geneticallyengineered variant proteins. A variant protein in the context of thepresent invention is exemplified by the B. lentus protease of SEQ IDNO:11, which is a variant of the naturally-occurring protein B. lentusprotease GG36 (SEQ ID NO:9), from which it differs by three amino acidsubstitutions at positions 74, 101 and 102 of the mature region. Anotherexample of a variant protease is the B. clausii protease SEQ ID NO:19,which is a variant of the naturally-occurring protein B. clausiiprotease Maxacal (SEQ ID NO:13), from which it differs by two amino acidsubstitutions at positions 99 and 102 of the mature region (FIG. 1).

As used herein, “homolog” and “homologous protein” refers to a protein(e.g., protease) that has similar action and/or structure, as a proteinof interest (e.g., a protease from another source). It is not intendedthat homologs be necessarily related evolutionarily. Thus, it isintended that the term encompass the same or similar enzyme(s) (i.e., interms of structure and function) obtained from different species.

The terms “derived from” and “obtained from” refer to not only aprotease produced or producible by a strain of the organism in question,but also a protease encoded by a DNA sequence isolated from such strainand produced in a host organism containing such DNA sequence.Additionally, the term refers to a protease which is encoded by a DNAsequence of synthetic and/or cDNA origin and which has the identifyingcharacteristics of the protease in question. To exemplify, “proteasesderived from Bacillus” refers to those enzymes having proteolyticactivity which are naturally-produced by Bacillus, as well as to serineproteases like those produced by Bacillus sources but which through theuse of genetic engineering techniques are produced by non-Bacillusorganisms transformed with a nucleic acid encoding said serineproteases.

A “modified full-length protease”, a “modified precursor protease” or a“modified protease” are interchangeably used to refer to a full-lengthprotease that comprises a signal peptide, a mature region and a proregion that are derived from a parent or precursor protease, wherein thepro region is modified to contain at least one mutation. In someembodiments, the pro region and the mature region are derived from thesame parent protease. In other embodiments, the pro region and themature region are derived from different parent proteases. The modifiedprotease comprises a pro region that is modified to contain at least onemutation, and it is encoded by a modified polynucleotide. The amino acidsequence of the modified protease is said to be “generated” from theparent protease amino acid sequence by introducing into the pro regionof the parent amino acid sequence at least one mutation e.g. asubstitution, deletion or insertion of one or more amino acids. In someembodiments, one or more amino acids of the pro region of the precursorprotease are substituted to generate the modified full-length protease.Such modification is of the “precursor” DNA sequence which encodes theamino acid sequence of the “precursor” protease rather than manipulationof the precursor protease per se.

The term “unmodified” when used in reference to a protease polypeptideor polynucleotide, herein refers to a protease comprising a pro regionthat has not been modified to comprise at least one mutation e.g. asubstitution.

The terms “full-length protein” and “pre-pro-protein” herein refer to agene product comprising a signal peptide, a pro sequence and a maturesequence. For example, the full-length protease of SEQ ID NO:59comprises the signal peptide (pre region) (SEQ ID NO:3, encoded forexample by the pre polynucleotide of SEQ ID NO:2), the pro region (SEQID NO:7, encoded for example by the pre polynucleotide of SEQ ID NO:6),and the mature region (SEQ ID NO:9 encoded by the polynucleotide of SEQID NO:8).

The term “signal sequence”, “signal peptide” or “pre region” refers toany sequence of nucleotides and/or amino acids which may participate inthe secretion of the mature or precursor forms of the protein. Thisdefinition of signal sequence is a functional one, meant to include allthose amino acid sequences encoded by the N-terminal portion of theprotein gene, which participate in the effectuation of the secretion ofprotein. To exemplify, a pre peptide of a protease of the presentinvention at least includes the amino acid sequence identical toresidues 1-29 of SEQ ID NO:3.

The term “pro sequence” or “pro region” is an amino acid sequencebetween the signal sequence and mature protease that is necessary forthe secretion/production of the protease. Cleavage of the pro sequencewill result in a mature active protease. To exemplify, a pro region of aprotease of the present invention at least includes the amino acidsequence identical to residues 1-84 of the pro region of SEQ ID NO:7,which correspond to amino acids 30-113 of the full-length protease ofSEQ ID NO:59.

The terms “mature form” or “mature region” refer to the final functionalportion of the protein. To exemplify, a mature form of the protease ofthe present invention includes the amino acid sequence identical toresidues 1-269 of SEQ ID NO:9. In this context, the “mature form” is“processed from” a full-length protease, wherein the processing of thefull-length protease encompasses the removal of the signal peptide andthe removal of the pro region.

The terms “pro-protein”, “pro-polypeptide” and “pro-protease”, hereinrefer to a protein comprising the mature form operably linked to apro-polypeptide. A “pro-polypeptide” is encoded by a“pro-polynucleotide”.

As used herein, the term “heterologous protein” refers to a protein orpolypeptide that does not naturally occur in the host cell. Similarly, a“heterologous polynucleotide” refers to a polynucleotide that does notnaturally occur in the host cell. Heterologous polypeptides and/orheterologous polynucleotides include chimeric polypeptides and/orpolynucleotides.

As used herein, “substituted” and “substitutions” refer toreplacement(s) of an amino acid residue or nucleic acid base in a parentsequence. In some embodiments, the substitution involves the replacementof a naturally occurring residue or base. The modified proteases hereinencompass the substitution of any one of the 84 amino acids of the proregion of the precursor protease by any one of the remaining nineteenamino acids. For example, the substitution at position 6 (E6) is areplacement of a glutamic acid (E) with one of the group consisting ofalanine (A), cysteine (C), aspartic acid (D), glycine (G), phenylalanine(F), histidine (H), isoleucine (I), lysine (K), leucine (L), methionine(M), asparagine (N), proline (P), glutamine (Q), arginine (R), serine(S), threonine (T), valine (V), thryptophan (W), and tyrosine (Y). Asubstitution of an amino acid e.g. E6, for any other amino acid at thesame position is denoted by E6X, wherein X is one of the remaining 19amino acids that substitutes E at position 6. In some embodiments, twoor more amino acids are substituted to generate a modified protease thatcomprises a combination of amino acid substitutions. For example, acombination of a substitution of amino acid E at position 6 for aminoacid A in combination with the substitution of amino acid E at position30 for amino acid T is denoted as E6A-E30T. Amino acid positions for thesubstitutions in the pro region are numbered corresponding to thenumbered position in the pro region of SEQ ID NO:7.

As used herein, “by correspondence to”, “corresponding to,” or“equivalent to” refers to a residue at the enumerated position in aprotein or peptide, or a residue that is analogous, homologous, orequivalent to an enumerated residue in a protein or peptide. As usedherein, “corresponding region,” generally refers to an analogousposition along related proteins or a reference protein.

The terms “pre polynucleotide”, “pro nucleotide” and “maturepolynucleotide” herein refer to the polynucleotide sequences thatrespectively encode for the pre, pro and mature regions of a proteine.g. a protease.

The term “production” with reference to a protease, encompasses the twoprocessing steps of a full-length protease including: 1. the removal ofthe signal peptide, which is known to occur during protein secretion;and 2. the removal of the pro region, which creates the active matureform of the enzyme and which is known to occur during the maturationprocess (Wang et al., Biochemistry 37:3165-3171 (1998); Power et al.,Proc Natl Acad Sci USA 83:3096-3100 [1986]). The term “enhancedproduction” herein refers to the production of a mature protease that isprocessed from a modified full-length protease, and which occurs at alevel that is greater than the level of production of the same matureprotease when processed from an unmodified full-length protease.

The term “processed” with reference to a mature protease refers to thematuration process that a full-length protein e.g. a full-lengthprotease, undergoes to become an active mature enzyme.

“Activity” with respect to enzymes means “catalytic activity” andencompasses any acceptable measure of enzyme activity, such as the rateof activity, the amount of activity, or the specific activity. Catalyticactivity refers to the ability to catalyze a specific chemical reaction,such as the hydrolysis of a specific chemical bond. As the skilledartisan will appreciate, the catalytic activity of an enzyme onlyaccelerates the rate of an otherwise slow chemical reaction. Because theenzyme only acts as a catalyst, it is neither produced nor consumed bythe reaction itself. The skilled artisan will also appreciate that notall polypeptides have a catalytic activity. “Specific activity” is ameasure of activity of an enzyme per unit of total protein or enzyme.Thus, specific activity may be expressed by unit weight (e.g. per gram,or per milligram) or unit volume (e.g. per ml) of enzyme. Further,specific activity may include a measure of purity of the enzyme, or canprovide an indication of purity, for example, where a standard ofactivity is known, or available for comparison. The amount of activityreflects to the amount of enzyme that is produced by the host cell thatexpresses the enzyme being measured.

The term “relative activity” or “ratio of production” are used hereininterchangeably to refer to the ratio of the enzymatic activity of amature protease that was processed from a modified protease to theenzymatic activity of a mature protease that was processed from anunmodified protease. The ratio of production is determined by dividingthe value of the activity of the protease processed from a modifiedprecursor by the value of the activity of the same protease whenprocessed from an unmodified precursor. The relative activity is theratio of production expressed as a percentage.

As used herein, the term “expression” refers to the process by which apolypeptide is produced based on the nucleic acid sequence of a gene.The process includes both transcription and translation.

The term “percent (%) identity” is defined as the percentage of aminoacid/nucleotide residues in a candidate sequence that are identical withthe amino acid residues/nucleotide residues of the precursor sequence(i.e., the parent sequence). A % amino acid sequence identity value isdetermined by the number of matching identical residues divided by thetotal number of residues of the “longer” sequence in the aligned region.Amino acid sequences may be similar, but are not “identical” where anamino acid is substituted, deleted, or inserted in the subject sequencerelative to the reference sequence. For proteins, the percent sequenceidentity is preferably measured between sequences that are in a similarstate with respect to posttranslational modification. Typically, the“mature sequence” of the subject protein, i.e., that sequence whichremains after processing to remove a signal sequence, is compared to amature sequence of the reference protein. In other instances, aprecursor sequence of a subject polypeptide sequence may be compared tothe precursor of the reference sequence.

As used herein, the term “promoter” refers to a nucleic acid sequencethat functions to direct transcription of a downstream gene. In someembodiments, the promoter is appropriate to the host cell in which thetarget gene is being expressed. The promoter, together with othertranscriptional and translational regulatory nucleic acid sequences(also termed “control sequences”) is necessary to express a given gene.In general, the transcriptional and translational regulatory sequencesinclude, but are not limited to, promoter sequences, ribosomal bindingsites, transcriptional start and stop sequences, translational start andstop sequences, and enhancer or activator sequences.

A nucleic acid or a polypeptide is “operably linked” when it is placedinto a functional relationship with another nucleic acid or polypeptidesequence, respectively. For example, a promoter or enhancer is operablylinked to a coding sequence if it affects the transcription of thesequence; a ribosome binding site is operably linked to a codingsequence if it is positioned so as to facilitate translation; or amodified pro region is operably linked to a mature region of a proteaseif it enables the processing of the full-length protease to produce themature active form of the enzyme. Generally, “operably linked” meansthat the DNA or polypeptide sequences being linked are contiguous.

A “host cell” refers to a suitable cell that serves as a host for anexpression vector comprising DNA according to the present invention. Asuitable host cell may be a naturally occurring or wild-type host cell,or it may be an altered host cell. In one embodiment, the host cell is aGram positive microorganism. In some embodiments, the term refers tocells in the genus Bacillus.

As used herein, “Bacillus sp.” includes all species within the genus“Bacillus,” as known to those of skill in the art, including but notlimited to B. subtilis, B. licheniformis, B. lentus, B. brevis, B.pumilis, B. stearothermophilus, B. alkalophilus, B. amyloliquefaciens,B. clausii, B. halodurans, B. megaterium, B. coagulans, B. circulans, B.lautus, and B. thuringiensis. It is recognized that the genus Bacilluscontinues to undergo taxonomical reorganization. Thus, it is intendedthat the genus include species that have been reclassified, includingbut not limited to such organisms as B. stearothermophilus, which is nownamed “Geobacillus stearothermophilus.” The production of resistantendospores in the presence of oxygen is considered the defining featureof the genus Bacillus, although this characteristic also applies to therecently named Alicyclobacillus, Amphibacillus, Aneurinibacillus,Anoxybacillus, Brevibacillus, Filobacillus, Gracilibacillus,Halobacillus, Paenibacillus, Salibacillus, Thermobacillus, Ureibacillus,and Virgibacillus.

The terms “polynucleotide” and “nucleic acid”, used interchangeablyherein, refer to a polymeric form of nucleotides of any length. Theseterms include, but are not limited to, a single-, double-stranded DNA,genomic DNA, cDNA, or a polymer comprising purine and pyrimidine bases,or other natural, chemically, biochemically modified, non-natural orderivatized nucleotide bases. Non-limiting examples of polynucleotidesinclude genes, gene fragments, chromosomal fragments, ESTs, exons,introns, mRNA, tRNA, rRNA, ribozymes, cDNA, recombinant polynucleotides,branched polynucleotides, plasmids, vectors, isolated DNA of anysequence, isolated RNA of any sequence, nucleic acid probes, andprimers. It will be understood that, as a result of the degeneracy ofthe genetic code, a multitude of nucleotide sequences encoding a givenprotein may be produced.

As used herein, the terms “DNA construct” and “transforming DNA” areused interchangeably to refer to DNA used to introduce sequences into ahost cell or organism. The DNA construct may be generated in vitro byPCR or any other suitable technique(s) known to those in the art. Insome embodiments, the DNA construct comprises a sequence of interest(e.g., a sequence encoding a modified protease). In some embodiments,the sequence is operably linked to additional elements such as controlelements (e.g., promoters, etc.). The DNA construct may further comprisea selectable marker. In some embodiments, the DNA construct comprisessequences homologous to the host cell chromosome. In other embodiments,the DNA construct comprises non-homologous sequences. Once the DNAconstruct is assembled in vitro it may be used to mutagenize a region ofthe host cell chromosome (i.e., replace an endogenous sequence with aheterologous sequence).

As used herein, the term “expression cassette” refers to a nucleic acidconstruct generated recombinantly or synthetically, with a series ofspecified nucleic acid elements that permit transcription of aparticular nucleic acid in a target cell. The recombinant expressioncassette can be incorporated into a vector such as a plasmid,chromosome, mitochondrial DNA, plastid DNA, virus, or nucleic acidfragment. Typically, the recombinant expression cassette portion of anexpression vector includes, among other sequences, a nucleic acidsequence to be transcribed and a promoter. In some embodiments,expression vectors have the ability to incorporate and expressheterologous DNA fragments in a host cell. Many prokaryotic andeukaryotic expression vectors are commercially available. Selection ofappropriate expression vectors is within the knowledge of those of skillin the art. The term “expression cassette” is used interchangeablyherein with “DNA construct,” and their grammatical equivalents.Selection of appropriate expression vectors is within the knowledge ofthose of skill in the art.

As used herein, the term “heterologous DNA sequence” refers to a DNAsequence that does not naturally occur in a host cell. In someembodiments, a heterologous DNA sequence is a chimeric DNA sequence thatis comprised of parts of different genes, including regulatory elements.

As used herein, the term “vector” refers to a polynucleotide constructdesigned to introduce nucleic acids into one or more cell types. Vectorsinclude cloning vectors, expression vectors, shuttle vectors, andplasmids. In some embodiments, the polynucleotide construct comprises aDNA sequence encoding the full-length protease (e.g., modified proteaseor unmodified precursor protease). As used herein, the term “plasmid”refers to a circular double-stranded (ds) DNA construct used as acloning vector, and which forms an extrachromosomal self-replicatinggenetic element in some eukaryotes or prokaryotes, or integrates intothe host chromosome.

As used herein in the context of introducing a nucleic acid sequenceinto a cell, the term “introduced” refers to any method suitable fortransferring the nucleic acid sequence into the cell. Such methods forintroduction include but are not limited to protoplast fusion,transfection, transformation, conjugation, and transduction (See e.g.,Ferrari et al., “Genetics,” in Hardwood et al, (eds.), Bacillus, PlenumPublishing Corp., pages 57-72, [1989]).

As used herein, the terms “transformed” and “stably transformed” refersto a cell that has a non-native (heterologous) polynucleotide sequenceintegrated into its genome or as an episomal plasmid that is maintainedfor at least two generations.

Modified Proteases

The present invention provides methods and compositions for theproduction of mature proteases in bacterial host cells. The compositionsinclude modified polynucleotides that encode modified proteases, whichhave at least one mutation in the pro region; the modified serineproteases encoded by the modified polynucleotides; expression cassettes,DNA constructs, and vectors comprising the modified polynucleotides thatencode the modified proteases; and the bacterial host cells transformedwith the vectors of the invention. The methods include methods forenhancing the production of mature proteases in bacterial host cellse.g. Bacillus sp. host cells. The produced proteases find use in theindustrial production of enzymes, suitable for use in variousindustries, including but not limited to the cleaning, animal feed andtextile processing industry.

The basic mechanism by which proteins are transported across membranesappears to be universal, with important features conserved betweenbacteria and eukaryotes. Because they can secrete certain proteins inlarge quantities into the growth medium, Bacillus species are used forthe industrial production of enzymes such as alkaline serine proteases.Proteases are produced in vivo from a precursor protease known as apre-pro-protease, which comprises a pre region, also known as signalpeptide, a pro region and a mature region of the protease. Proteinsecretion across the Bacillus sp. cell envelope is a complex processthat includes insertion of the precursor protein into the membrane andtranslocation of the protein across the membrane. The pre region servesas a signal peptide for protein secretion across the membrane and ishydrolyzed by a signal peptidase. The extracellular part of thematuration process involves folding of the pro-protease, self-processingof the pro region, and degradation of the pro-region to create theactive mature form of the enzyme (Nagarjan V. Protein Secretion in“Bacillus subtilis and other Gram-Positive Bacteria” Ch. 49, p 713-726[1993]; Ruan et al., Biochemistry, 38:8562-8571 [2009]).

In some embodiments, the invention provides a modified polynucleotideencoding a modified protease that is generated by introducing at leastone mutation in the pro polynucleotide of the precursor protease. Themodified polynucleotide is generated from a precursor polynucleotidethat comprises a polynucleotide encoding the pro region of the protease(pro polynucleotide), and a polynucleotide encoding the mature region ofthe protease (mature polynucleotide), wherein the pro polynucleotide ismodified to contain at least one mutation to generate a modifiedpolynucleotide that encodes the modified protease of the invention. Theprecursor polynucleotide further comprises a polynucleotide encoding asignal peptide (pre polynucleotide). The pre, pro and mature regions ofthe unmodified protease can be derived from a wild-type or variantparent protease of animal, vegetable or microbial origin. In someembodiments, the pro and mature regions of the unmodified precursorprotease are derived from one parent protease, while the pre region isderived from a different parent protease. In other embodiments, the pre,pro and mature regions are derived from three different parentproteases. In some embodiments, the parent protease is of bacterialorigin. In some embodiments, the parent protease is a protease of thesubtilisin type (subtilases, subtilopeptidases, EC 3.4.21.62), whichcomprise catalytically active amino acids, also referred to as serineproteases. In some embodiments, the parent protease is a Bacillus sp.protease. Preferably, the parent protease is a serine protease derivedfrom Bacillus clausii, or Bacillus lentus.

Precursor Polynucleotides Encoding Precursor Proteases

In some embodiments, the unmodified precursor polynucleotide encodes afull-length protease comprising the mature region of a parent protease,such as a protease derived from Bacillus clausii and Bacillus lentus,homologs and variants thereof, operably linked to a polynucleotide e.g.gctgaagaagcaaaagaaaaatatttaattggctttaatgagcaggaagctgtcagtgagtttgtagaacaagtagaggcaaatgacgaggtcgccattctctctgaggaagaggaagtcgaaattgaattgcttcatgaatttgaaacgattcctgttttatccgttgagttaagcccagaagatgtggacgcgcttgaactcgatccagcgatttcttatattgaagaggatgcagaagtaacgacaatg(SEQ ID NO:6), that encodes the pro region of SEQ ID NO:7AEEAKEKYLIGFNEQEAVSEFVEQVEANDEVAILSEEEEVEIELLHEFETIPVLSVELSPEDVDALELDPAISYIEEDAEVTTM (SEQ ID NO:7). Examples of mature parent proteasesinclude the wild-type B. lentus proteaseAQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALNNSIGVLGVAPSAELYAVKVLGASGSGSVSSIAQGLEWAGNNGMHVANLSLGSPSPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR (SEQ ID NO:9), and variants thereof suchas The protease of SEQ ID NO:11AQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALDNSIGVLGVAPSAELYAVKVLGASGSGAISSIAQGLEWAGNNGMHVANLSLGSPSPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR (SEQ ID NO:11); the wild-type Bacillusclausii PB92 protease Maxacal (U.S. Pat. No. 5,217,878)AQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALNNSIGVLGVAPNAELYAVKVLGASGSGSVSSIAQGLEWAGNNGMHVANLSLGSPSPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR; (SEQ ID NO:13), and variants thereof suchas

the protease of SEQ ID NO:15AQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALNNSIGVLGVAPNAELYAVKVLGASGSGSVSSIAQGLEWAGNNVMHVANLSLGLQAPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR; (SEQ ID NO:15),the protease of SEQ ID NO:17AQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALNNSIGVLGVAPNAELYAVKVLGASGMGSVSSIAQGLEWAGNNVMHVANLSLGLQAPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR; (SEQ ID NO:17),the protease of SEQ ID NO:19AQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALNNSIGVLGVAPNAELYAVKVLGASGGGSNSSIAQGLEWAGNNGMHVANLSLGSPSPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR; (SEQ ID NO:19),the protease of SEQ ID NO:21AQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALDNSIGVLGVAPRAELYAVKVLGASGSGSVSSIAQGLEWAGNNRMHVANLSLGLQAPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR; (SEQ ID NO:21),the protease of SEQ ID NO:23AQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALDNSIGVLGVAPRAELYAVKVLGASGSGSVSSIAQGLEWAGNNRMHVANLSLGLQAPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRADFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNRQIRNHLKNTATSLGSTNLYGSGLVNAEAATR; (SEQ ID NO:23), andthe protease of SEQ ID NO:25AQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALDNSIGVLGVAPRAELYAVKVLGASGSGSVSSIAQGLEWAGNNGMHVANLSLGLQAPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRADFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRRHLKNTATSLGSTNLYGSGLVNAEAATR; (SEQ ID NO:25).Examples of polynucleotides encoding the mature proteases of SEQ IDNOS:9, 11, 13, 15, 17, 19, 21, 23 and 25 are SEQ ID NOS:8, 10, 12, 14,16, 18, 20, 22, and 24, respectively, shown in FIG. 5. It is understoodthat a polypeptide may be coded for by more than one nucleotide sequencedue to the degeneracy of the genetic code.

The mature proteases of SEQ ID NOS: 9, 11, 13, 15, 17, 19, 21, 23 and 25differ from each other by up to 9 amino acids (FIG. 1). In someembodiments, the pro polypeptide of SEQ ID NO:7 is naturally andoperably linked to the mature sequences of SEQ ID NOS: 9, 11, 13, 15,17, 19, 21, 23 and 25. Thus, in some embodiments, the precursorpolynucleotides comprise polynucleotides encoding the pro region of SEQID NO:7 is operably linked to a mature region chosen from SEQ ID NOS: 9,11, 13, 15, 17, 19, 21, 23 and 25, resulting in the pro-proteases of SEQID NOS:38-46, respectively:

SEQ ID NO: 38: SEQ ID NO: 38)AEEAKEKYLIGFNEQEAVSEFVEQVEANDEVAILSEEEEVEIELLHEFETIPVLSVELSPEDVDALELDPAISYIEEDAEVTTMAQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALNNSIGVLGVAPSAELYAVKVLGASGSGSVSSIAQGLEWAGNNGMHVANLSLGSPSPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR;, SEQ ID NO: 39:SEQ ID NO: 39)AEEAKEKYLIGFNEQEAVSEFVEQVEANDEVAILSEEEEVEIELLHEFETIPVLSVELSPEDVDALELDPAISYIEEDAEVTTMAQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALDNSIGVLGVAPSAELYAVKVLGASGSGAISSIAQGLEWAGNNGMHVANLSLGSPSPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR; SEQ ID NO: 40:SEQ ID NO: 40)AEEAKEKYLIGFNEQEAVSEFVEQVEANDEVAILSEEEEVEIELLHEFETIPVLSVELSPEDVDALELDPAISYIEEDAEVTTMAQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALNNSIGVLGVAPNAELYAVKVLGASGSGSVSSIAQGLEWAGNNGMHVANLSLGSPSPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR;; SEQ ID NO: 41:SEQ ID NO: 41)AEEAKEKYLIGFNEQEAVSEFVEQVEANDEVAILSEEEEVEIELLHEFETIPVLSVELSPEDVDALELDPAISYIEEDAEVTTMAQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALNNSIGVLGVAPNAELYAVKVLGASGSGSVSSIAQGLEWAGNNVMHVANLSLGLQAPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR;; SEQ ID NO: 42:SEQ ID NO: 42)AEEAKEKYLIGFNEQEAVSEFVEQVEANDEVAILSEEEEVEIELLHEFETIPVLSVELSPEDVDALELDPAISYIEEDAEVTTMAQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALNNSIGVLGVAPNAELYAVKVLGASGMGSVSSIAQGLEWAGNNVMHVANLSLGLQAPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR;, SEQ ID NO: 43:SEQ ID NO: 43)AEEAKEKYLIGFNEQEAVSEFVEQVEANDEVAILSEEEEVEIELLHEFETIPVLSVELSPEDVDALELDPAISYIEEDAEVTTMAQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALNNSIGVLGVAPNAELYAVKVLGASGGGSNSSIAQGLEWAGNNGMHVANLSLGSPSPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR;, SEQ ID NO: 44:SEQ ID NO: 44)AEEAKEKYLIGFNEQEAVSEFVEQVEANDEVAILSEEEEVEIELLHEFETIPVLSVELSPEDVDALELDPAISYIEEDAEVTTMAQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALDNSIGVLGVAPRAELYAVKVLGASGSGSVSSIAQGLEWAGNNRMHVANLSLGLQAPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR;; SEQ ID NO: 45:SEQ ID NO: 45)AEEAKEKYLIGFNEQEAVSEFVEQVEANDEVAILSEEEEVEIELLHEFETIPVLSVELSPEDVDALELDPAISYIEEDAEVTTMAQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALDNSIGVLGVAPRAELYAVKVLGASGSGSVSSIAQGLEWAGNNRMHVANLSLGLQAPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRADFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNRQIRNHLKNTATSLGSTNLYGSGLVNAEAATR;; and SEQ ID NO: 46:(SEQ ID NO: 46)AEEAKEKYLIGFNEQEAVSEFVEQVEANDEVAILSEEEEVEIELLHEFETIPVLSVELSPEDVDALELDPAISYIEEDAEVTTMAQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALDNSIGVLGVAPRAELYAVKVLGASGSGSVSSIAQGLEWAGNNGMHVANLSLGLQAPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRADFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRRHLKNTATSLGSTNLYGSGLVNAEAATR.

Other mature parent proteases that are operably linked to the propolypeptide of SEQ ID NO:7, comprise homologs of mature proteases fromBacillus sp. such as P27693_(—) Bacillus _(—) alcalophilus e.g. SEQ IDNO:47, P20724_(—) Bacillus_sp_YAB e.g. SEQ ID NO:48, BAA25184_(—)Bacillus_sp e.g. SEQ ID NO:49, YP_(—)174261_(—) B _(—) clausii_KSM-K16e.g. SEQ ID NO:50, BAA06157 Bacillus sp G-825-6 (SEQ ID NO:51) andBAF34115_A_transvaalensis e.g. SEQ ID NO:52 (FIG. 3). In someembodiments, the unmodified precursor polynucleotide encodes a precursorprotease comprising the mature region of a protease that is at leastabout 60%, at least about 65%, at least about 70%, at least about 75%,at least about 80%, at least about 85%, at least about 90%, at leastabout 95%, at least about 97%, at least about 98%, at least about 99%identical to the mature region of SEQ ID NO:9, 11, 13, 15, 17, 19, 21,23 and 25 which is operably linked to the pro polypeptide of SEQ IDNO:7.

Subjecting the amino acid sequence of the pro region of SEQ ID NO:7 to aBLAST query revealed that in addition to being identical to the proregion of the naturally-occurring pro region of the P41362 B. clausiiand P27693 Bacillus alkalophilus (FIG. 2), the pro region of SEQ ID NO:7has a high degree of identity with the amino acid sequence of the proregion of proteases from as GG36 B. lentus 267048, (SEQ ID NO:53),P20724_(—) Bacillus_sp_YAB (SEQ ID NO:54), BAA25184_(—) Bacillus_sp (SEQID NO:55), YP_(—)174261_(—) B _(—) clausii_KSM-K16 e.g. SEQ ID NO:56,BAA06157 Bacillus sp G-825-6 (SEQ ID NO:57) andBAF34115_A_transvaalensis e.g. SEQ ID NO:58, (FIG. 2). It is expectedthat mutations made in the pro region of SEQ ID NOS:53-58 andcorresponding to the mutations of SEQ ID NO:7 that enhance theproduction of the mature protease to which it is operably linked, willenhance the production of the mature protease to which the pro region ofSEQ ID NOs:53-58 is operably linked. Thus, in some embodiments, theunmodified precursor polynucleotide comprises a pro polynucleotideencoding a pro polypeptide that is chosen from SEQ ID NOS:53-58 and thatis operably linked to the mature protease of SEQ ID NO:9, variants andhomologs thereof. For example, the pro polynucleotide encoding a propolypeptide chosen from SEQ ID NOS:53-58 is operably linked to a variantof the mature protease of SEQ ID NO:9 e.g. SEQ ID NOS:11, 13, 15, 17,18, 21, 23, and 25. Similarly, the pro polynucleotide encoding a propolypeptide chosen from SEQ ID NOS:53-58 is operably linked to a homologof the mature protease of SEQ ID NO:9 e.g. SEQ ID NOS: SEQ ID NO:47-52.In other embodiments, the unmodified precursor polynucleotide comprisesa pro polynucleotide encoding a pro polypeptide that is at least about60%, at least about 65%, at least about 70%, at least about 75%, atleast about 80%, at least about 85%, at least about 90%, at least about95%, at least about 97% or at least about 99% identical to that of SEQID NO:7 operably linked to the mature protease of SEQ ID NO:9 or any oneof SEQ ID NOS: 11, 13, 15, 17, 18, 21, 23, and 25 and 47-52.

The percent identity shared by polynucleotide or polypeptide sequencesis determined by direct comparison of the sequence information betweenthe molecules by aligning the sequences and determining the identity bymethods known in the art. An example of an algorithm that is suitablefor determining sequence similarity is the BLAST algorithm, which isdescribed in Altschul, et al., J. Mol. Biol., 215:403-410 (1990).Software for performing BLAST analyses is publicly available through theNational Center for Biotechnology Information. This algorithm involvesfirst identifying high scoring sequence pairs (HSPs) by identifyingshort words of length W in the query sequence that either match orsatisfy some positive-valued threshold score T when aligned with a wordof the same length in a database sequence. These initial neighborhoodword hits act as starting points to find longer HSPs containing them.The word hits are expanded in both directions along each of the twosequences being compared for as far as the cumulative alignment scorecan be increased. Extension of the word hits is stopped when: thecumulative alignment score falls off by the quantity X from a maximumachieved value; the cumulative score goes to zero or below; or the endof either sequence is reached. The BLAST algorithm parameters W, T, andX determine the sensitivity and speed of the alignment. The BLASTprogram uses as defaults a wordlength (W) of 11, the BLOSUM62 scoringmatrix (See, Henikoff & Henikoff, Proc. Natl. Acad. Sci. USA 89:10915(1989)) alignments (B) of 50, expectation (E) of 10, M′S, N′-4, and acomparison of both strands.

The BLAST algorithm then performs a statistical analysis of thesimilarity between two sequences (See e.g., Karlin and Altschul, Proc.Nat'l. Acad. Sci. USA 90:5873-5787 [1993]). One measure of similarityprovided by the BLAST algorithm is the smallest sum probability (P(N)),which provides an indication of the probability by which a match betweentwo nucleotide or amino acid sequences would occur by chance. Forexample, a nucleic acid is considered similar to a serine proteasenucleic acid of this invention if the smallest sum probability in acomparison of the test nucleic acid to a serine protease nucleic acid isless than about 0.1, more preferably less than about 0.01, and mostpreferably less than about 0.001. Where the test nucleic acid encodes aserine protease polypeptide, it is considered similar to a specifiedserine protease nucleic acid if the comparison results in a smallest sumprobability of less than about 0.5, and more preferably less than about0.2.

The pro region of SEQ ID NO:7 was used to search the NCBI non-redundantprotein database (version Mar. 26, 2009). The command line BLAST program(version 2.2.17) was used with default parameters. The obtainedsequences that were found to have sequences similar to the pro region(SEQ ID NO:7) were divided into pro regions and mature regions, whichwere further analyzed as follows to generate the alignments shown inFIGS. 2 and 3.

The alignments of the amino acid sequences of the pro region (FIG. 2)and the mature region (FIG. 3) of various serine proteases to the proregion (SEQ ID NO:7) and mature region of GG36 (SEQ ID NO:9) wereobtained using the multiple alignment programs ClustalW and MUSCLE. Thealignment was first performed using the program ClustalW (version 1.83)with default parameters. The alignment was refined five times using theprogram MUSCLE (version 3.51) with default parameters. Only the regionscorresponding to the mature region or pro region of were chosen in thealignment. The percent identity was calculated as the number ofidentical residues aligned between the two sequences in question dividedby the number of residues aligned in the alignment. As discussed above,the alignments show that there are several pro and mature sequences thatshare a high degree of amino acid identity to that of the pro (SEQ IDNO:7) and mature (SEQ ID NO:9) regions of GG36.

In some embodiments, in addition to encoding the pro-protease, theunmodified precursor polynucleotide further comprises a prepolynucleotide encoding a signal peptide, which is operably linked tothe pro-protease. In some embodiments, the signal peptide is the AprEsignal peptide VRSKKLWISLLFALTLIFTMAFSNMSAQA (SEQ ID NO: 3) encoded bythe polynucleotide ofgtgagaagcaaaaaattgtggatcagcttgttgtttgcgttaacgttaatctttacgatggcgttcagcaacatgtctgcgcaggct(SEQ ID NO:2). In other embodiments, the signal peptide is a fusionsignal peptide VRSKKLWIVASTALLISVAFSSSIASA (SEQ ID NO:5) encoded by thepolynucleotide ofgtgagaagcaaaaaattgtggatcgtcgcgtcgaccgcactactcatttctgttgcttttagttcatcgatcgcatcggct(SEQ ID NO:4). In yet other embodiments, the precursor polynucleotidecomprises the polynucleotide that encodes the signal peptide that isnaturally and operably linked to the pro-protease. Any signal sequencethat can effectuate efficient secretion of a modified protease in aBacillus sp host cell can be operably linked to a pro-protease of theinvention. Such signal peptides include signal peptides of bacterialorigin that direct secretion of proteins via bacterial secretionpathways e.g. Sec pathway, TAT pathway, and eukaryotic signal sequencesthat are applicable for expressing proteins in prokaryotic host cells(EP1481059B1).

Modified Polynucleotides Encoding Modified Proteases

The unmodified precursor polynucleotide described above, is modified toencode a modified protease by introducing at least one mutation at anyone of amino acids at positions 1-84 of the pro polypeptide of SEQ IDNO:7, which is operably linked to a mature protease. In someembodiments, the at least one mutation is an amino acid substitution.

In some embodiments, the modified polynucleotide encodes an amino acidsubstitution at least at one amino acid position selected from positions1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20,21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38,39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56,57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74,75, 76, 77, 78, 79, 80, 81, 82, 83, and 84, of the pro polypeptide ofSEQ ID NO:7, operably linked to a mature protease that is at least 60%identical to the mature protease of SEQ ID NO:9. In some embodiments,the mature protease is at least about 65%, at least about 70%, at leastabout 75%, at least about 80%, at least about 85%, at least about 90%,at least about 95%, at least about 97%, at least about 98%, at leastabout 99% identical to the mature region of SEQ ID NO:9. Matureproteases that are at least 60% identical to the mature protease of SEQID NO:9 (B. lentus protease GG36), include the wild-type Bacillusclausii PB92 protease Maxacal (SEQ ID NO:13), and variants thereof suchas SEQ ID NO:11, SEQ ID NO:15, SEQ ID NO:17, SEQ ID NO:19, SEQ ID NO:21,SEQ ID NO:23, and SEQ ID NO:25; and homologs of SEQ ID NO:9 includinghomologs of mature proteases from Bacillus sp. such as P27693_(—)Bacillus _(—) alcalophilus e.g. SEQ ID NO:47, P20724_(—) Bacillus_sp_YABe.g. SEQ ID NO:48, BAA25184_(—) Bacillus_sp e.g. SEQ ID NO:49,YP_(—)174261_(—) B _(—) clausii_KSM-K16 e.g. SEQ ID NO:50, BAA06157Bacillus sp G-825-6 (SEQ ID NO:51) and BAF34115_A_transvaalensis e.g.SEQ ID NO:52, (FIG. 3). Preferably, the modified pro polynucleotideencodes a mutation at least at one amino acid at position chosen frompositions 6, 30 and 32 of the pro polypeptide of SEQ ID NO: 7, which isoperably linked to the mature protease of any one of the proteases ofSEQ ID NOS: 9, 11, 13, 15, 17, 19, 21, 23, and 25. The at least onemutation is an amino acid substitution of the glutamic acid (E) atposition 6 and/or 30; and/or the amino acid substitution of the alanine(A) at position 32. It is intended that any of the other 19 amino acidsthat substitute the glutamic acid (E) at position 6 and/or 30, and/orthe alanine (A) at position 32 of the pro region of SEQ ID NO:7 may beused to encode a modified protease from which the mature form isproduced at a level that is greater than that obtained from processingof the corresponding unmodified precursor protein. In some embodiments,the at least one mutation is a substitution chosen from the followingsubstitutions:

E6A, E6R, E6C, E6Q, E6H, E6I, E6K, E6L, E6M, E6S, E6Y, E6N, E6G, E6F,E6P, E6T, E6W, E6V, E30A, E30R, E30N, E30D, E30G, E30H, E30L, E30K,E30F, E30S, E30T, E30V, E30R, E30Q, E30G, E30I, E30L, E30M, E30F, E30P,E30T, E30W, E30Y, E30C, E30M, E30F E30V, A32K, A32T, A32Q, A32S, A32V,A32L, and A32F of the pro polypeptide of the SEQ ID NO:7. For example,any one of the substitutions chosen from E6A, E6R, E6C, E6Q, E6H, E6I,E6K, E6M, E6S, E6Y, E30A, E30R, E30N, E30D, E30Q, E30G, E30L, E30M,E30P, E30S, E30T, E30W, E30Y, E30V, A32, A32R, A32C, A32E, A32G, A32L,A32K, A32F, A32T, A32Y, and A32V are made in the pro region of SEQ IDNO:7 to produce the mature protease of SEQ ID NO:17; any one of thesubstitutions chosen from E6A, E6R, E6N, E6C, E6Q, E6G, E6H, E6M, E6F,E6P, E6S, E6T, E6W, E6V, A32K, A32T, and A32V, are made in the proregion of SEQ ID NO:7 to produce the mature protease of SEQ ID NO:9; anyone of the substitutions chosen from E6A, E6H, E6K, and E6R, E30A, E30R,E30N, E30D, E30G, E30H, E30L, E30K, E30F, E30S, E30T, and E30V, are madein the pro region of SEQ ID NO:7 to produce the mature protease of SEQID NO:19; any one of the substitutions chosen from E6A, E6R, E6Q, E6G,E6L, E6K, E6M, E6F, E6T, E6V, E30R, E30Q, E30G, E30I, E30L, E30M, E30F,E30P, E30T, E30W, E30Y, E30V, A32Q, A32S, A32T, and A32V, are made inthe pro region of SEQ ID NO:7 to produce the mature protease of SEQ IDNO:11; and any one of the substitutions chosen from E30A, E30R, E30N,E30D, E30C, E30G, E30H, E30M, E30F, E30S, E30W, A32L, A32F, and A32V,are made in the pro region of SEQ ID NO:7 to produce the mature proteaseof SEQ ID NO:21. The at least one substitution enhances the productionof the mature protease when compared to the production of the matureprotease expressed from a precursor protease that does not comprise theat least one substitution in the pro region of SEQ ID NO:7 to which itis operably linked.

In some other embodiments, the modification of the pro region of SEQ IDNO:7 includes a combination of mutations. For example, modification ofthe pro region of SEQ ID NO:7 includes a combination of at least twosubstitutions. In other embodiments, modification of the pro region ofSEQ ID NO:7 includes a combination of at least three, at least four, atleast five, at least six, at least seven, at least 8, at least nine, orat least 10 substitutions. Modifications of the pro region also includea combination of at least one substitution and one deletion; acombination of at least one substitution and at least one insertion; acombination of at least one insertion and one deletion, and acombination of at least one substitution, at least one deletion, and atleast one insertion. Preferably, the modification of the pro region ofSEQ ID NO:7 includes at least two substitutions that result in acombination of substitutions at positions 6 and 30 (i.e. E6X-E30X), 6and 32 (i.e. E6X-A32X) or 30 and 32 (i.e. E30X-A32X). For example, themodified polynucleotide encodes a pro region comprising a combination ofsubstitutions chosen from E6R-A32K, E6N-A32K, E6D-A32K, E6I-A32K,E6K-A32K, E6M-A32K, E6P-A32K, E6S-A32K, E6T-A32K, E6N-A32K, E30W-A32K,E30V-A32K, E6A-E30G, E6R-E30G, E6C-E30G, E6Q-E30G, E6G-E30G, E6H-E30G,E6K-E30G, E6S-E30G, E6W-E30G, E30G-A32R, E30G-A32Q, E30G-A32E,E30G-A32G, E30G-A32H, E30G-A32I, E30G-A32K, E30G-A32S, E30G-A32T,E30G-A32W, E30G-A32V, E6G-E30G-A32E, E6G-E30G-A32S, E6G-E30G-A32T,E6G-E30G-A32W, E6A-E30G, E6R-E30G, E6N-E30G, E6D-E30G, E6C-E30G,E6Q-E30G, E6G-E30G, E6H-E30G, E6K-E30G, E6M-E30G, E6F-E30G, E6P-E30G,E6S-E30G, E6T-E30G, E6W-E30G, E6V-E30G, E6Y-E30G, E6A-E30S, E6G-E30S,E6L-E30S, E6K-E30S, E6F-E30S, E6P-E30S, E6Y-E30S, E6V-E30S, E30S-A32R,E30S-A32N, E30S-A32D, E30S-A32C, E30S-A32Q, E30S-A32E, E30S-A32G,E30S-A32H, E30S-A32L, E30S-A32K, E30S-A32M, E30S-A32F, E30S-A32P,E30S-A32S, E30S-A32T, E30S-A32W, E30S-A32Y, and E30S-A32V. For example,modification of the pro region of SEQ ID NO:7 includes a combination ofat least two substitutions chosen from E6R-A32K, E6N-A32K, E6D-A32K,E6I-A32K, E6K-A32K, E6M-A32K, E6P-A32K, E6S-A32K, E6T-A32K, E6N-A32K,E30W-A32K, and E30V-A32K to produce the mature protease of SEQ ID NO:9;modification of the pro region of SEQ ID NO:7 includes a combination ofat least two substitutions chosen from E6A-E30G, E6R-E30G, E6C-E30G,E6Q-E30G, E6G-E30G, E6H-E30G, E6K-E30G, E6S-E30G, E6W-E30G, E30G-A32R,E30G-A32Q, E30G-A32E, E30G-A32G, E30G-A32H, E30G-A32I, E30G-A32K,E30G-A32S, E30G-A32T, E30G-A32W, E30G-A32V to produce the matureprotease of SEQ ID NO:17; modification of the pro region of SEQ ID NO:7includes a combination of at least two substitutions chosen fromE6A-E30G, E6R-E30G, E6N-E30G, E6D-E30G, E6C-E30G, E6Q-E30G, E6G-E30G,E6H-E30G, E6K-E30G, E6M-E30G, E6F-E30G, E6P-E30G, E6S-E30G, E6T-E30G,E6W-E30G, E6V-E30G, E6Y-E30G to produce the mature protease of SEQ IDNO:19; and modification of the pro region of SEQ ID NO:7 includes acombination of at least two substitutions chosen from E6A-E30S,E6G-E30S, E6L-E30S, E6K-E30S, E6F-E30S, E6P-E30S, E6Y-E30S, E6V-E30S,E30S-A32R, E30S-A32N, E30S-A32D, E30S-A32C, E30S-A32Q, E30S-A32E,E30S-A32G, E30S-A32H, E30S-A32L, E30S-A32K, E30S-A32M, E30S-A32F,E30S-A32P, E30S-A32S, E30S-A32T, E30S-A32W, E30S-A32Y, and E30S-A32V toproduce the mature protease of SEQ ID NO:21. Other examples ofmodifications of the pro region of SEQ ID NO:7 include at least threesubstitutions that result in a combination of substitutions at positions6, 30 and 32 (i.e. E6X-E30X-A32X). For example, modification of the proregion of SEQ ID NO:7 includes a combination of at least threesubstitutions chosen from E6G-E30G-A32E, E6G-E30G-A32S, E6G-E30G-A32T,E6G-E30G-A32W to produce the mature protease of SEQ ID NO:17. The atleast two or three substitutions enhance the production of the matureprotease when compared to the production of the mature proteaseexpressed from a precursor protease that does not comprise the at leasttwo or three substitutions in the pro region of SEQ ID NO:7 to which itis operably linked.

Several methods are known in the art that are suitable for generatingmodified polynucleotide sequences of the present invention, includingbut not limited to site-saturation mutagenesis, scanning mutagenesis,insertional mutagenesis, deletion mutagenesis, random mutagenesis,site-directed mutagenesis, and directed-evolution, as well as variousother recombinatorial approaches. The commonly used methods include DNAshuffling (Stemmer W P, Proc Natl Acad Sci USA. 25; 91(22):10747-51[1994]), methods based on non-homologous recombination of genes e.g.ITCHY (Ostermeier et al., Bioorg Med. Chem. 7(10):2139-44 [1999]),SCRACHY (Lutz et al. Proc Natl Acad Sci USA. 98(20):11248-53 [2001]),SHIPREC (Sieber et al., Nat. Biotechnol. 19(5):456-60 [2001]), and NRR(Bittker et al., Nat. Biotechnol. 20(10):1024-9 [2001]; Bittker et al.,Proc Natl Acad Sci USA. 101(18):7011-6 [2004]), and methods that rely onthe use of oligonucleotides to insert random and targeted mutations,deletions and/or insertions (Ness et al., Nat. Biotechnol. 20(12):1251-5[2002]; Coco et al., Nat. Biotechnol. 20(12):1246-50 [2002]; Zha et al.,Chembiochem. 3; 4(1):34-9 [2003], Glaser et al., J. Immunol.149(12):3903-13 [1992], Sondek and Shortie, Proc Natl Acad Sci USA89(8):3581-5 [1992], Yáñez et al., Nucleic Acids Res. 32(20):e158[2004], Osuna et al., Nucleic Acids Res. 32(17):e136 [2004], Gaytán etal., Nucleic Acids Res. 29(3):E9 [2001], and Gaytán et al., NucleicAcids Res. 30(16):e84 [2002]).

In addition to encoding the modified pro-protease, the modifiedprecursor polynucleotide further comprises a pre polynucleotide encodinga signal peptide. In some embodiments, the signal peptide is the AprEsignal peptide (SEQ ID NO:3) encoded by the polynucleotide of SEQ IDNO:2. For example, full-length modified precursor proteases include theproteases of SEQ ID NOS:, wherein the pro region of said precursorproteases comprises at least one mutation. In some embodiments, the atleast one mutation is an amino acid substitution is made at the positionequivalent to position 6, 30 or 32 of the pro region of SEQ ID NO:7.Alternatively, the signal peptide is a fusion signal peptide of SEQ IDNO:5 encoded by the polynucleotide of SEQ ID NO:4. Signal peptides thatare naturally linked to the mature protease may also be used to expressthe full-length modified proteases described herein. Examples offull-length precursor proteases that can be modified to comprise atleast one amino acid substitution at a position chosen from 6, 30 and 32of the pro region of SEQ ID NO:7 include:

the full-length protease of SEQ ID NO:59VRSKKLWISLLFALTLIFTMAFSNMSAQAAEEAKEKYLIGFNEQEAVSEFVEQVEANDEVAILSEEEEVEIELLHEFETIPVLSVELSPEDVDALELDPAISYIEEDAEVTTMAQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALNNSIGVLGVAPSAELYAVKVLGASGSGSVSSIAQGLEWAGNNGMHVANLSLGSPSPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR; SEQ ID NO:59);the full-length protease of SEQ ID NO:60VRSKKLWISLLFALTLIFTMAFSNMSAQAAEEAKEKYLIGFNEQEAVSEFVEQVEANDEVAILSEEEEVEIELLHEFETIPVLSVELSPEDVDALELDPAISYIEEDAEVTTMAQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALDNSIGVLGVAPSAELYAVKVLGASGSGAISSIAQGLEWAGNNGMHVANLSLGSPSPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR; SEQ ID NO:60);the full-length protease of SEQ ID NO:61VRSKKLWISLLFALTLIFTMAFSNMSAQAAEEAKEKYLIGFNEQEAVSEFVEQVEANDEVAILSEEEEVEIELLHEFETIPVLSVELSPEDVDALELDPAISYIEEDAEVTTMAQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALNNSIGVLGVAPNAELYAVKVLGASGSGSVSSIAQGLEWAGNNGMHVANLSLGSPSPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR; SEQ ID NO:61);the full-length protease of SEQ ID NO:62VRSKKLWISLLFALTLIFTMAFSNMSAQAAEEAKEKYLIGFNEQEAVSEFVEQVEANDEVAILSEEEEVEIELLHEFETIPVLSVELSPEDVDALELDPAISYIEEDAEVTTMAQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALNNSIGVLGVAPNAELYAVKVLGASGSGSVSSIAQGLEWAGNNVMHVANLSLGLQAPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR; SEQ ID NO:62);the full-length protease of SEQ ID NO:63VRSKKLWISLLFALTLIFTMAFSNMSAQAAEEAKEKYLGFNEQEAVSEFVEQVEANDEVAILSEEEEVEIELLHEFETIPVLSVELSPEDVDALELDPAISYIEEDAEVTTMAQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALNNSIGVLGVAPNAELYAVKVLGASGMGSVSSIAQGLEWAGNNVMHVANLSLGLQAPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR; SEQ ID NO:63);the full-length protease of SEQ ID NO:64VRSKKLWISLLFALTLIFTMAFSNMSAQAAEEAKEKYLIGFNEQEAVSEFVEQVEANDEVAILSEEEEVEIELLHEFETIPVLSVELSPEDVDALELDPAISYIEEDAEVTTMAQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALNNSIGVLGVAPNAELYAVKVLGASGGGSNSSIAQGLEWAGNNGMHVANLSLGSPSPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR; SEQ ID NO:64);the full-length protease of SEQ ID NO:65VRSKKLWISLLFALTLIFTMAFSNMSAQAAEEAKEKYLIGFNEQEAVSEFVEQVEANDEVAILSEEEEVEIELLHEFETIPVLSVELSPEDVDALELDPAISYIEEDAEVTTMAQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALDNSIGVLGVAPRAELYAVKVLGASGSGSVSSIAQGLEWAGNNRMHVANLSLGLQAPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR; SEQ ID NO:65),the full-length protease of SEQ ID NO:66VRSKKLWISLLFALTLIFTMAFSNMSAQAAEEAKEKYLIGFNEQEAVSEFVEQVEANDEVAILSEEEEVEIELLHEFETIPVLSVELSPEDVDALELDPAISYIEEDAEVTTMAQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALDNSIGVLGVAPRAELYAVKVLGASGSGSVSSIAQGLEWAGNNRMHVANLSLGLQAPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRADFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNRQIRNHLKNTATSLGSTNLYGSGLVNAEAAT; SEQ ID NO:66), andthe full-length protease of SEQ ID NO:67VRSKKLWISLLFALTLIFTMAFSNMSAQAAEEAKEKYLIGFNEQEAVSEFVEQVEANDEVAILSEEEEVEIELLHEFETIPVLSVELSPEDVDALELDPAISYIEEDAEVTTMAQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALDNSIGVLGVAPRAELYAVKVLGASGSGSVSSIAQGLEWAGNNGMHVANLSLGLQAPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRADFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRRHLKNTATSLGSTNLYGSGLVNAEAATR; SEQ ID NO:67).The pre region (signal peptide; SEQ ID NO:3) is shown in bold, the proregion (SEQ ID NO:7) is underlined, and the mature region is italicized.

As previously described, in addition to being identical to thenaturally-occurring pro region of the P41362 B. clausii and P27693Bacillus alkalophilus (FIG. 2), the pro region of SEQ ID NO:7 has a highdegree of identity with the amino acid sequence of the pro region ofproteases from as GG36 B. lentus 267048, (SEQ ID NO:53), P20724_(—)Bacillus_sp_YAB SEQ ID NO:54), BAA25184_(—) Bacillus_sp (SEQ ID NO:55),YP_(—)174261_(—) B _(—) clausii_KSM-K16 e.g. SEQ ID NO:56, BAA06157Bacillus sp G-825-6 (SEQ ID NO:57) and BAF34115_A_transvaalensis e.g.SEQ ID NO:58, (FIG. 2). It is expected that mutations made in the proregion of SEQ ID NOs:53-58 and corresponding to the mutations of SEQ IDNO:7 that enhance the production of the mature protease to which it isoperably linked, will enhance the production of the mature protease towhich the modified pro region of SEQ ID NOs: 53-58 is operably linked.For example, any one of the modified polynucleotides that encode the proregion of SEQ ID NOs: 53-58 can be modified to encode an amino acidsubstitution at least at one amino acid position selected from positions1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20,21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38,39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56,57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74,75, 76, 77, 78, 79, 80, 81, 82, 83, and 84, wherein the position isnumbered by correspondence with the amino acid sequence of the propolypeptide of SEQ ID NO:7. Preferably, any one of the modifiedpolynucleotides that encode the pro region of SEQ ID NOs: 53-58 ismodified to encode a mutation at least at one amino acid at positionchosen from positions 6, 30 and 32. In some embodiments, the at leastone mutation chosen from positions 6, 30 and 32 is a substitution chosenfrom the following substitutions: E6A, E6R, E6C, E6Q, E6H, E6I, E6K,E6L, E6M, E6S, E6Y, E6N, E6G, E6F, E6P, E6T, E6W, E6V, E30A, E30R, E30N,E30D, E30G, E30H, E30L, E30K, E30F, E30S, E30T, E30V, E30R, E30Q, E30G,E30I, E30L, E30M, E30F, E30P, E30T, E30W, E30Y, E30C, E30M, E30F E30V,A32K, A32T, A32Q, A32S, A32V, A32 L, and A32F, wherein the positions arenumbered by correspondence with the amino acid sequence of the propolypeptide of the SEQ ID NO:7. In other embodiments, the modifiedpolynucleotide encodes a pro region comprising a combination ofsubstitutions chosen from a combination of substitutions made atpositions 6 and 32 (i.e. E6X-E30X), at positions 30 and 32 (i.e.E30X-A32X). For example, the modified polynucleotide encodes a proregion comprising a combination of substitutions chosen from E6R-A32K,E6N-A32K, E6D-A32K, E6I-A32K, E6K-A32K, E6M-A32K, E6P-A32K, E6S-A32K,E6T-A32K, E6N-A32K, E30W-A32K, E30V-A32K, E6A-E30G, E6R-E30G, E6C-E30G,E6Q-E30G, E6G-E30G, E6H-E30G, E6K-E30G, E6S-E30G, E6W-E30G, E30G-A32R,E30G-A32Q, E30G-A32E, E30G-A32G, E30G-A32H, E30G-A32I, E30G-A32K,E30G-A32S, E30G-A32T, E30G-A32W, E30G-A32V, E6G-E30G-A32E,E6G-E30G-A32S, E6G-E30G-A32T, E6G-E30G-A32W, E6A-E30G, E6R-E30G,E6N-E30G, E6D-E30G, E6C-E30G, E6Q-E30G, E6G-E30G, E6H-E30G, E6K-E30G,E6M-E30G, E6F-E30G, E6P-E30G, E6S-E30G, E6T-E30G, E6W-E30G, E6V-E30G,E6Y-E30G, E6A-E30S, E6G-E30S, E6L-E30S, E6K-E30S, E6F-E30S, E6P-E30S,E6Y-E30S, E6V-E30S, E30S-A32R, E30S-A32N, E30S-A32D, E30S-A32C,E30S-A32Q, E30S-A32E, E30S-A32G, E30S-A32H, E30S-A32L, E30S-A32K,E30S-A32M, E30S-A32F, E30S-A32P, E30S-A32S, E30S-A32T, E30S-A32W,E30S-A32Y, and E30S-A32V, wherein the positions are numbered bycorrespondence with the amino acid sequence of the pro polypeptide ofthe SEQ ID NO:7. In yet other embodiments, the modified polynucleotideencodes a pro region comprising a combination of substitutions chosenfrom E6G-E30G-A32E, E6G-E30G-A32S, E6G-E30G-A32T, E6G-E30G-A32W, whereinthe positions are numbered by correspondence with the amino acidsequence of the pro polypeptide of the SEQ ID NO:7. Any one of the proregions of SEQ ID NOS:7 and 53-58 that is modified to contain the atleast one two or three substitutions as described above, is operablylinked to a mature protease that is at least 60% identical to the matureprotease of SEQ ID NO:9. Mature proteases that are at least 60%identical to the mature protease of SEQ ID NO:9 (B. lentus proteaseGG36), include the wild-type Bacillus clausii PB92 protease Maxacal (SEQID NO:13), and variants thereof such as SEQ ID NO:11, SEQ ID NO:15, SEQID NO:17, SEQ ID NO:19, SEQ ID NO:21, SEQ ID NO:23, and SEQ ID NO:25;and homologs of SEQ ID NO:9 including homologs of mature proteases fromBacillus sp. such as P27693_(—) Bacillus _(—) alcalophilus e.g. SEQ IDNO:47, P20724_(—) Bacillus_sp_YAB e.g. SEQ ID NO:48, BAA25184_(—)Bacillus_sp e.g. SEQ ID NO:49, YP_(—)174261_(—) B _(—) clausii_KSM-K16e.g. SEQ ID NO:50, BAA06157 Bacillus sp G-825-6 (SEQ ID NO:51) andBAF34115_A_transvaalensis e.g. SEQ ID NO:52, (FIG. 3).

Any one of the pro regions of SEQ ID NOS: 7 and 53-58 that is modifiedto contain the at least one substitution described above, and that isoperably linked to a mature protease that is at least 60% identical tothe mature protease of SEQ ID NO:9, is further operably linked to asignal peptide. Preferably, the signal peptide is the AprE signalpeptide (SEQ ID NO:3) encoded by the polynucleotide of SEQ ID NO:2.Alternatively, the signal peptide is a fusion signal peptideVRSKKLWIVASTALLISVAFSSSIASA (SEQ ID NO:5) encoded by the polynucleotideof SEQ ID NO:4gtgagaagcaaaaaattgtggatcgtcgcgtcgaccgcactactcatttctgttgcttttagttcatcgatcgcatcggct(SEQ ID NO:4). Any signal sequence that can effectuate efficientsecretion of a modified protease in a Bacillus sp host cell can beoperably linked to a pro-protease of the invention. Such signal peptidesinclude signal peptides of bacterial origin that direct secretion ofproteins via bacterial secretion pathways e.g. Sec pathway, TAT pathway,and eukaryotic signal sequences that are applicable for expressingproteins in prokaryotic host cells (EP1481059B1).

The at least one amino acid substitution at position 6, 30, and/or 32made in the pro region of SEQ ID NO:7 can be introduced at equivalentamino acid positions in the pro regions of a pre-pro-protease to enhancethe production of the mature enzyme, wherein the signal peptide can bechosen from the signal peptides of SEQ ID NOS: 3, and 5, signal peptidesthat are naturally and operably linked to the pro-protease, and anysignal sequence that can effectuate efficient secretion of a modifiedprotease in a Bacillus sp host cell e.g. Bacillus subtilis.

As indicated above, in some embodiments, the present invention providesvectors comprising the aforementioned modified polynucleotides. In someembodiments, the vector is an expression vector in which the modifiedpolynucleotide sequence encoding the modified protease of the inventionis operably linked to additional segments required for efficient geneexpression (e.g., a promoter operably linked to the gene of interest).In some embodiments, these necessary elements are supplied as the gene'sown homologous promoter if it is recognized, (i.e., transcribed by thehost), and a transcription terminator that is exogenous or is suppliedby the endogenous terminator region of the protease gene. In someembodiments, a selection gene such as an antibiotic resistance gene thatenables continuous cultural maintenance of plasmid-infected host cellsby growth in antimicrobial-containing media is also included.

In some embodiments, the expression vector is derived from plasmid orviral DNA, or in alternative embodiments, contains elements of both.Exemplary vectors include, but are not limited to pXX, pC194, pJH101,pE194, pHP13 (Harwood and Cutting (eds), Molecular Biological Methodsfor Bacillus, John Wiley & Sons, [1990], in particular, chapter 3;suitable replicating plasmids for B. subtilis include those listed onpage 92; Perego, M. (1993) Integrational Vectors for GeneticManipulations in Bacillus subtilis, p. 615-624; A. L. Sonenshein, J. A.Hoch, and R. Losick (ed.), Bacillus subtilis and other Gram-positivebacteria: biochemistry, physiology and molecular genetics, AmericanSociety for Microbiology, Washington, D.C.).

For expression and production of protein(s) of interest e.g. a protease,in a cell, at least one expression vector comprising at least one copyof a polynucleotide encoding the modified protease, and preferablycomprising multiple copies, is transformed into the cell underconditions suitable for expression of the protease. In some particularlyembodiments, the sequences encoding the proteases (as well as othersequences included in the vector) are integrated into the genome of thehost cell, while in other embodiments, the plasmids remain as autonomousextra-chromosomal elements within the cell. Thus, the present inventionprovides both extrachromosomal elements as well as incoming sequencesthat are integrated into the host cell genome. It is intended that eachof the vectors described herein will find use in the present invention.In some embodiments, the polynucleotide construct encoding the modifiedprotease is present on an integrating vector (e.g., pJH-GG36; FIG. 4)that enables the integration and optionally the amplification of themodified polynucleotide into the bacterial chromosome. Examples of sitesfor integration include, but are not limited to the aprE, the amyE, theveg or the pps regions. Indeed, it is contemplated that other sitesknown to those skilled in the art will find use in the presentinvention. In some embodiments, transcription of the polynucleotidesencoding the modified proteases is effectuated by a promoter that is thewild-type promoter for the selected precursor protease. In some otherembodiments, the promoter is heterologous to the precursor protease, butis functional in the host cell. Specifically, examples of suitablepromoters for use in bacterial host cells include but are not limited tothe amyE, amyQ, amyL, pstS, sacB, pSPAC, pAprE, pVeg, pHpalI promoters,the promoter of the B. stearothermophilus maltogenic amylase gene, theB. amyloliquefaciens (BAN) amylase gene, the B. subtilis alkalineprotease gene, the B. clausii alkaline protease gene the B. pumilisxylosidase gene, the B. thuringiensis cryIIIA, and the B. licheniformisalpha-amylase gene. In some embodiments, the promoter is the AprEpromoter having the sequence:

(SEQ ID NO: 1)gaattcctccattttcttctgctatcaaaataacagactcgtgattttccaaacgagctttcaaaaaagcctctgccccttgcaaatcggatgcctgtctataaaattcccgatattggttaaacagcggcgcaatggcggccgcatctgatgtctttgcttggcgaatgttcatcttatttcttcctccctctcaataattttttcattctatcccttttctgtaaagtttatttttcagaatacttttatcatcatgctttgaaaaaatatcacgataatatccattgttctcacggaagcacacgcaggtcatttgaacgaattttttcgacaggaatttgccgggactcaggagcatttaacctaaaaaagcatgacatttcagcataatgaacatttactcatgtctattttcgttcttttctgtatgaaaatagttatttcgagtctctacggaaatagcgagagatgatatacctaaatagagataaaatcatctcaaaaaaatgggtctactaaaatattattccatctattacaataaattcacagaatagtcttttaagtaagtctactctgaatttttttaaaaggagagggtaaaga.Additional promoters include, but are not limited to the A4 promoter, aswell as phage Lambda P_(R) or P_(L) promoters, and the E. coli lac, trpor tac promoters.

Precursor and modified proteases are produced in host cells of anysuitable Gram-positive microorganism, including bacteria and fungi. Forexample, in some embodiments, the modified protease is produced in hostcells of fungal and/or bacterial origin. In some embodiments, the hostcells are Bacillus sp., Streptomyces sp., Escherichia sp. or Aspergillussp. In some embodiments, the modified proteases are produced by Bacillussp. host cells. Examples of Bacillus sp. host cells that find use in theproduction of the modified proteins of the present invention include,but are not limited to B. licheniformis, B. lentus, B. subtilis, B.amyloliquefaciens, B. lentus, B. brevis, B. stearothermophilus, B.alkalophilus, B. coagulans, B. circulans, B. pumilis, B. thuringiensis,B. clausii, and B. megaterium, as well as other organisms within thegenus Bacillus. In some embodiments, B. subtilis host cells find use.U.S. Pat. Nos. 5,264,366 and 4,760,025 (RE 34,606) describe variousBacillus host strains that find use in the present invention, althoughother suitable strains find use in the present invention.

Several industrial strains that find use in the present inventioninclude non-recombinant (i.e., wild-type) Bacillus sp. strains, as wellas variants of naturally occurring strains and/or recombinant strains.In some embodiments, the host strain is a recombinant strain, wherein apolynucleotide encoding a polypeptide of interest has been introducedinto the host. In some embodiments, the host strain is a B. subtilishost strain and particularly a recombinant Bacillus subtilis hoststrain. Numerous B. subtilis strains are known, including but notlimited to 1A6 (ATCC 39085), 168 (1A01), SB19, W23, Ts85, B637, PB1753through PB1758, PB3360, JH642, 1A243 (ATCC 39,087), ATCC 21332, ATCC6051, MI113, DE100 (ATCC 39,094), GX4931, PBT 110, and PEP 211 strain(See e.g., Hoch et al., Genetics, 73:215-228 [1973]) (See also, U.S.Pat. No. 4,450,235; U.S. Pat. No. 4,302,544; and EP 0134048; each ofwhich is incorporated by reference in its entirety). The use of B.subtilis as an expression host well known in the art (See e.g., See,Palva et al., Gene 19:81-87 [1982]; Fahnestock and Fischer, J.Bacteriol., 165:796-804 [1986]; and Wang et al., Gene 69:39-47 [1988]).

In some embodiments, the Bacillus host is a Bacillus sp. that includes amutation or deletion in at least one of the following genes, degU, degS,degR and degQ. Preferably the mutation is in a degU gene, and morepreferably the mutation is degU(Hy)32. (See e.g., Msadek et al., J.Bacteriol., 172:824-834 [1990]; and Olmos et al., Mol. Gen. Genet.,253:562-567 [1997]). A preferred host strain is a Bacillus subtiliscarrying a degU32(Hy) mutation. In some further embodiments, theBacillus host comprises a mutation or deletion in scoC4, (See, e.g.,Caldwell et al., J. Bacteriol., 183:7329-7340 [2001]); spoIIE (See,Arigoni et al., Mol. Microbiol., 31:1407-1415 [1999]); and/or oppA orother genes of the opp operon (See e.g., Perego et al., Mol. Microbiol.,5:173-185 [1991]). Indeed, it is contemplated that any mutation in theopp operon that causes the same phenotype as a mutation in the oppA genewill find use in some embodiments of the altered Bacillus strain of thepresent invention. In some embodiments, these mutations occur alone,while in other embodiments, combinations of mutations are present. Insome embodiments, an altered Bacillus that can be used to produce themodified proteases of the invention is a Bacillus host strain thatalready includes a mutation in one or more of the above-mentioned genes.In addition, Bacillus sp. host cells that comprise mutation(s) and/ordeletions of endogenous protease genes find use. In some embodiments,the Bacillus host cell comprises a deletion of the aprE and the nprEgenes. In other embodiments, the Bacillus sp. host cell comprises adeletion of 5 protease genes (US20050202535), while in otherembodiments, the Bacillus sp. host cell comprises a deletion of 9protease genes (US20050202535).

Host cells are transformed with modified polynucleotides encoding themodified proteases of the present invention using any suitable methodknown in the art. Whether the modified polynucleotide is incorporatedinto a vector or is used without the presence of plasmid DNA, it isintroduced into a microorganism, in some embodiments, preferably an E.coli cell or a competent Bacillus cell. Methods for introducing DNA intoBacillus cells involving plasmid constructs and transformation ofplasmids into E. coli are well known. In some embodiments, the plasmidsare subsequently isolated from E. coli and transformed into Bacillus.However, it is not essential to use intervening microorganisms such asE. coli, and in some embodiments, a DNA construct or vector is directlyintroduced into a Bacillus host.

Those of skill in the art are well aware of suitable methods forintroducing polynucleotide sequences into Bacillus cells (See e.g.,Ferrari et al., “Genetics,” in Harwood et al. (ed.), Bacillus, PlenumPublishing Corp. [1989], pages 57-72; Saunders et al., J. Bacteriol.,157:718-726 [1984]; Hoch et al., J. Bacteriol., 93:1925-1937 [1967];Mann et al., Current Microbiol., 13:131-135 [1986]; and Holubova, FoliaMicrobiol., 30:97 [1985]; Chang et al., Mol. Gen. Genet., 168:11-115[1979]; Vorobjeva et al., FEMS Microbiol. Lett., 7:261-263 [1980]; Smithet al., Appl. Env. Microbiol., 51:634 [1986]; Fisher et al., Arch.Microbiol., 139:213-217 [1981]; and McDonald, J. Gen. Microbiol.,130:203 [1984]). Indeed, such methods as transformation, includingprotoplast transformation and congression, transduction, and protoplastfusion are known and suited for use in the present invention. Methods oftransformation are used to introduce a DNA construct provided by thepresent invention into a host cell. Methods known in the art totransform Bacillus, include such methods as plasmid marker rescuetransformation, which involves the uptake of a donor plasmid bycompetent cells carrying a partially homologous resident plasmid(Contente et al., Plasmid 2:555-571 [1979]; Haima et al., Mol. Gen.Genet., 223:185-191 [1990]; Weinrauch et al., J. Bacteriol.,154:1077-1087 [1983]; and Weinrauch et al., J. Bacteriol., 169:1205-1211[1987]). In this method, the incoming donor plasmid recombines with thehomologous region of the resident “helper” plasmid in a process thatmimics chromosomal transformation.

In addition to commonly used methods, in some embodiments, host cellsare directly transformed (i.e., an intermediate cell is not used toamplify, or otherwise process, the DNA construct prior to introductioninto the host cell). Introduction of the DNA construct into the hostcell includes those physical and chemical methods known in the art tointroduce DNA into a host cell without insertion into a plasmid orvector. Such methods include, but are not limited to calcium chlorideprecipitation, electroporation, naked DNA, liposomes and the like. Inadditional embodiments, DNA constructs are co-transformed with aplasmid, without being inserted into the plasmid. In furtherembodiments, a selective marker is deleted from the altered Bacillusstrain by methods known in the art (See, Stahl et al., J. Bacteriol.,158:411-418 [1984]; and Palmeros et al., Gene 247:255-264 [2000]).

In some embodiments, the transformed cells of the present invention arecultured in conventional nutrient media. The suitable specific cultureconditions, such as temperature, pH and the like are known to thoseskilled in the art. In addition, some culture conditions may be found inthe scientific literature such as Hopwood (2000) Practical StreptomycesGenetics, John Innes Foundation, Norwich UK; Hardwood et al., (1990)Molecular Biological Methods for Bacillus, John Wiley and from theAmerican Type Culture Collection (ATCC).

In some embodiments, host cells transformed with polynucleotidesequences encoding modified proteases are cultured in a suitablenutrient medium under conditions permitting the expression of thepresent protease, after which the resulting protease is recovered fromthe culture. The medium used to culture the cells comprises anyconventional medium suitable for growing the host cells, such as minimalor complex media containing appropriate supplements. Suitable media areavailable from commercial suppliers or may be prepared according topublished recipes (e.g., in catalogues of the American Type CultureCollection). In some embodiments, the protease produced by the cells isrecovered from the culture medium by conventional procedures, including,but not limited to separating the host cells from the medium bycentrifugation or filtration, precipitating the proteinaceous componentsof the supernatant or filtrate by means of a salt (e.g., ammoniumsulfate), chromatographic purification (e.g., ion exchange, gelfiltration, affinity, etc.). Thus, any method suitable for recoveringthe protease(s) of the present invention finds use in the presentinvention. Indeed, it is not intended that the present invention belimited to any particular purification method.

The protein produced by a recombinant host cell comprising a modifiedprotease of the present invention is secreted into the culture media. Insome embodiments, other recombinant constructions join the heterologousor homologous polynucleotide sequences to nucleotide sequence encoding aprotease polypeptide domain which facilitates purification of thesoluble proteins (Kroll D J et al (1993) DNA Cell Biol 12:441-53). Suchpurification facilitating domains include, but are not limited to, metalchelating peptides such as histidine-tryptophan modules that allowpurification on immobilized metals (Porath J (1992) Protein Expr Purif3:263-281), protein A domains that allow purification on immobilizedimmunoglobulin, and the domain utilized in the FLAGS extension/affinitypurification system (Immunex Corp, Seattle Wash.). The inclusion of acleavable linker sequence such as Factor XA or enterokinase (Invitrogen,San Diego Calif.) between the purification domain and the heterologousprotein also find use to facilitate purification.

As indicated above, the invention provides for modified full-lengthpolynucleotides that encode modified full-length proteases that areprocessed by a Bacillus host cell to produce the mature form at a levelthat is greater than that of the same mature protease when processedfrom an unmodified full-length enzyme by a Bacillus host cell grownunder the same conditions. The level of production is determined by thelevel of activity of the secreted enzyme.

One measure of production can be determined as relative activity, whichis expressed as a percent of the ratio of the value of the enzymaticactivity of the mature form when processed from the modified protease tothe value of the enzymatic activity of the mature form when processedfrom the unmodified precursor protease. A relative activity equal orgreater than 100% indicates that the mature form a protease that isprocessed from a modified precursor is produced at a level that is equalor greater than the level at which the same mature protease is producedbut when processed from an unmodified precursor. Thus, in someembodiments, the relative activity of a mature protease processed fromthe modified protease is at least about 100%, at least about 110%, atleast about 120%, at least about 130%, at least about 140%, at leastabout 150%, at least about 160%, at least about 170%, at least about180%, at least about 190%, at least about 200%, at least about 225%, atleast about 250%, at least about 275%, at least about 300%, at leastabout 325%, at least about 350%, at least about 375%, at least about400%, at least about 425%, at least about 450%, at least about 475%, atleast about 500%, at least about 525%, at least about 550%, at leastabout 575%, at least about 600%, at least about 625%, at least about650%, at least about 675%, at least about 700%, at least about 725%, atleast about 750%, at least about 800%, at least about 825%, at leastabout 850%, at least about 875%, at least about 850%, at least about875%, at least about 900%, and up to at least about 1000% or more whencompared to the corresponding production of the mature form of theprotease that was processed from the unmodified precursor protease.Alternatively, the relative activity is expressed as the ratio ofproduction which is determined by dividing the value of the activity ofthe protease processed from a modified precursor by the value of theactivity of the same protease when processed from an unmodifiedprecursor. Thus, in some embodiments, the ratio of production of amature protease processed from a modified precursor is at least about 1,at least about 1.1, at least about 1.2, at least about 1.3 at leastabout, 1.4, at least about 1.5, at least about 1.6, at least about 1.7,at least about 1.8, at least about 1.9, at least about 2, at least about2.25, at least about 2.5, at least about 2.75, at least about 3, atleast about 3.25, at least about 3.5, at least about 3.75, at leastabout, at least about 4.25, at least about 4.5, at least about 4.75, atleast about 5, at least about 5.25, at least about 5.5, at least about5.75, at least about 6, at least about 6.25, at least about 6.5, atleast about 6.75, at least about 7, at least about 7.25, at least about7.5, at least about 8, at least about 8.25, at least about 8.5, at leastabout 8.75, at least about 9, and up to at least about 10.

There are various assays known to those of ordinary skill in the art fordetecting and measuring activity of proteases. In particular, assays areavailable for measuring protease activity that are based on the releaseof acid-soluble peptides from casein or hemoglobin, measured asabsorbance at 280 nm or colorimetrically using the Folin method (Seee.g., Bergmeyer et al., “Methods of Enzymatic Analysis” vol. 5,Peptidases, Proteinases and their Inhibitors, Verlag Chemie, Weinheim[1984]). Some other assays involve the solubilization of chromogenicsubstrates (See e.g., Ward, “Proteinases,” in Fogarty (ed.)., MicrobialEnzymes and Biotechnology, Applied Science, London, [1983], pp 251-317).Other exemplary assays include, but are not limited tosuccinyl-Ala-Ala-Pro-Phe-para nitroanilide assay (SAAPFpNA) and the2,4,6-trinitrobenzene sulfonate sodium salt assay (TNBS assay). Numerousadditional references known to those in the art provide suitable methods(See e.g., Wells et al., Nucleic Acids Res. 11:7911-7925 [1983];Christianson et al., Anal. Biochem., 223:119-129 [1994]; and Hsia etal., Anal Biochem., 242:221-227 [1999]). It is not intended that thepresent invention be limited to any particular assay method(s).

Other means for determining the levels of production of a matureprotease in a host cell include, but are not limited to methods that useeither polyclonal or monoclonal antibodies specific for the protein.Examples include, but are not limited to enzyme-linked immunosorbentassays (ELISA), radioimmunoassays (RIA), fluorescent immunoassays (FIA),and fluorescent activated cell sorting (FACS). These and other assaysare well known in the art (See e.g., Maddox et al., J. Exp. Med.,158:1211 [1983]).

All publications and patents mentioned herein are herein incorporated byreference. Various modifications and variations of the described methodand system of the invention will be apparent to those skilled in the artwithout departing from the scope and spirit of the invention. Althoughthe invention has been described in connection with specificembodiments, it should be understood that the invention as should not beunduly limited to such specific embodiments. Indeed, variousmodifications of the described modes for carrying out the invention thatare obvious to those skilled in the art and/or related fields areintended to be within the scope of the present invention.

EXPERIMENTAL

In the experimental disclosure which follows, the followingabbreviations apply: ppm (parts per million); M (molar); mM(millimolar); μM (micromolar); nM (nanomolar); mol (moles); mmol(millimoles); pmol (micromoles); nmol (nanomoles); gm (grams); mg(milligrams); μg (micrograms); pg (picograms); L (liters); ml and mL(milliliters); μl and μL (microliters); cm (centimeters); mm(millimeters); μm (micrometers); nm (nanometers); U (units); V (volts);MW (molecular weight); sec (seconds); min(s) (minute/minutes); h(s) andhr(s) (hour/hours); ° C. (degrees Centigrade); QS (quantity sufficient);QC (QuikChange), ND (not done); NA (not applicable); rpm (revolutionsper minute); w/v (weight to volume); v/v (volume to volume); g(gravity); OD (optical density); aa (amino acid); by (base pair); kb(kilobase pair); kD (kilodaltons); suc-AAPF-pNA(succinyl-L-alanyl-L-alanyl-L-prolyl-L-phenyl-alanyl-para-nitroanilide);DMSO (dimethyl sulfoxide); cDNA (copy or complementary DNA); DNA(deoxyribonucleic acid); ssDNA (single stranded DNA); dsDNA (doublestranded DNA); dNTP (deoxyribonucleotide triphosphate); DTT(1,4-dithio-DL-threitol); H2O (water); dH2O (deionized water); HCl(hydrochloric acid); MgCl₂ (magnesium chloride); MOPS(3-[N-morpholino]propanesulfonic acid); NaCl (sodium chloride); PAGE(polyacrylamide gel electrophoresis); PBS (phosphate buffered saline[150 mM NaCl, 10 mM sodium phosphate buffer, pH 7.2]); PEG (polyethyleneglycol); PCR (polymerase chain reaction); PMSF (phenylmethylsulfonylfluoride); RNA (ribonucleic acid); SDS (sodium dodecyl sulfate); Tris(tris(hydroxymethyl) aminomethane); SOC (2% Bacto-Tryptone, 0.5% BactoYeast Extract, 10 mM NaCl, 2.5 mM KCl); Terrific Broth (TB; 12 g/l BactoTryptone, 24 g/l glycerol, 2.31 g/l KH₂PO₄, and 12.54 g/l K₂HPO₄); OD280(optical density at 280 nm); OD600 (optical density at 600 nm); A405(absorbance at 405 nm); Vmax (the maximum initial velocity of an enzymecatalyzed reaction); HEPES(N-[2-Hydroxyethyl]piperazine-N-[2-ethanesulfonic acid]); Tris-HCl(tris[Hydroxymethyl]aminomethane-hydrochloride); TCA (trichloroaceticacid); HPLC (high pressure liquid chromatography); RP-HPLC (reversephase high pressure liquid chromatography); TLC (thin layerchromatography); EDTA (ethylenediaminetetracetic acid); EtOH (ethanol);SDS (sodium dodecyl sulfate); Tris (tris(hydroxymethyl)aminomethane); i(N,N,N′N′-tetraacetylethylenediamine).

The following examples are provided in order to demonstrate and furtherillustrate certain embodiments and aspects of the present invention andare not to be construed as limiting the scope thereof.

To determine the effect of amino acid substitutions in the alkalineprotease pro region on the production of the mature form of the proteaseto which the pro region is operably linked, one, two and three aminoacid substitutions were introduced at amino acids at positions 6, 30 and32 of the pro region of SEQ ID NO:7 when operably linked to the matureproteases of SEQ ID NOS:9, 11, 17, 19, and 21 as described in Examples1-5, respectively.

EXAMPLE 1 The Effect of Mutations in the Pro Region of SEQ ID NO:7 onthe Production of the Mature Alkaline Protease of SEQ ID NO:9

(a) Site-Saturation Mutagenesis of Amino Acids at Positions 6, 30 or 32of the Pro Region

Site-saturation mutagenesis of the pro region on the production of themature protease of SEQ ID NO:9 was performed using the QuikChange®site-directed mutagenesis kit (QC; Stratagene) according to thedirections of the manufacturer. A DNA cassette comprising the AprEpromoter, and the polynucleotide that encodes the full-length proteaseof SEQ ID NO:59 was cloned into the EcoRI and HindIII restriction sitesof the pJH101 vector (Ferrari et al. J. Bacteriol. 154:1513-1515 [1983])pJH-Pn (FIG. 4A) to generate the pJH-P9 plasmid. (Pn refers to the SEQID NO of the mature protease that is expressed from the pJH-Pn plasmid).The DNA cassette comprised the B. subtilis aprE promotergaattcctccattttcttctgctatcaaaataacagactcgtgattttccaaacgagctttcaaaaaagcctctgccccttgcaaatcggatgcctgtctataaaattcccgatattggttaaacagcggcgcaatggcggccgcatctgatgtctttgcttggcgaatgttcatcttatttcttcctccctctcaataattUttcattctatccatttctgtaaagtttatttttcagaatacttttatcatcatgctttgaaaaaatatcacgataatatccattgttctcacggaagcacacgcaggtcatttgaacgaattUttcgacaggaatttgccgggactcaggagcatttaacctaaaaaagcatgacatttcagcataatgaacatttactcatgtctattttcgttcttttctgtatgaaaatagttatttcgagtctctacggaaatagcgagagatgatatacctaaatagagataaaatcatctcaaaaaaatgggtctactaaaatattattccatctattacaataaattcacagaatagtatttaagtaagtctactctgaatttttttaaaaggagagggtaaaga (SEQID NO:1),

the polynucleotide sequencegtgagaagcaaaaaattgtggatcagcttgttgtttgcgttaacgttaatctttacgatggcgttcagcaacatgtctgcgcaggct(SEQ ID NO:2), which encodes the AprE signal peptideVRSKKLWISLLFALTLIFTMAFSNMSAQA (SEQ ID NO:3),

the polynucleotide sequencegctgaagaagcaaaagaaaaatatttaattggctttaatgagcaggaagctgtcagtgagtttgtagaacaagtagaggcaaatgacgaggtcgccattctctctgaggaagaggaagtcgaaattgaattgcttcatgaatttgaaacgattcctgttttatccgttgagttaagcccagaagatgtggacgcgcttgaactcgatccagcgatttcttatattgaagaggatgcagaagtaacgacaatg(SEQ ID NO:6), which encodes the unmodified pro regionAEEAKEKYLIGFNEQEAVSEFVEQVEANDEVAILSEEEEVEIELLHEFETIPVLSVELSPEDVDALELDPAISYIEEDAEVTTM (SEQ ID NO:7), and the polynucleotide sequencegcgcaatcagtgccatggggaattagccgtgtgcaagccccagctgcccataaccgtggattgacaggttctggtgtaaaagttgctgtcctcgatacaggtatttccactcatccagacttaaatattcgtggtggcgctagctttgtaccaggggaaccatccactcaagatgggaatgggcatggcacgcatgtggccgggacgattgctgctttaaacaattcgattggcgttcttggcgtagcgccgagcgcggaactatacgctgttaaagtattaggggcgagcggttcaggttcggtcagctcgattgcccaaggattggaatgggcagggaacaatggcatgcacgttgctaatttgagtttaggaagcccttcgccaagtgccacacttgagcaagctgttaatagcgcgacttctagaggcgttcttgttgtagcggcatctggaaattcaggtgcaggctcaatcagctatccggcccgttatgcgaacgcaatggcagtcggagctactgaccaaaacaacaaccgcgccagcttttcacagtatggcgcagggcttgacattgtcgcaccaggtgtaaacgtgcagagcacatacccaggttcaacgtatgccagcttaaacggtacatcgatggctactcctcatgttgcaggtgcagcagcccttgttaaacaaaagaacccatcttggtccaatgtacaaatccgcaatcatctaaagaatacggcaacgagcttaggaagcacgaacttgtatggaagcggacttgtcaatgcagaagctgcaactcgt (SEQ ID NO:8),which encodes the mature region of protease 9 (P9).AQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALNNSIGVLGVAPSAELYAVKVLGASGSGSVSSIAQGLEWAGNNGMHVANLSLGSPSPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR (SEQ ID NO:9).

Each of the 3 codons in the pro region of SEQ ID NO:7, exemplified byNNG/C, comprised in the full-length protease of SEQ ID NO:59, weremutated to be substituted by the 32 possible nucleotide triplets thatencode the 20 naturally occurring amino acids to generate threelibraries as follows. An aliquot of plasmid pJH-P9 DNA comprising thesequence encoding the full-length protease was mutated to generate afirst library of clones encoding all possible substitutions of glutamicacid (E) at position 6 (E6X) of the pro region (SEQ ID NO:7); a secondaliquot was mutated to generate a second library of clones encoding allpossible substitutions of glutamic acid (E) at position 30 (E30X) of thepro region (SEQ ID NO:7); and a third aliquot was mutated to generate athird library of clones encoding all possible substitutions of arginine(A) at position 32 (A32X) of the pro region (SEQ ID NO:7). Complementaryoverlapping primers were designed for mutating the codons of interestwith about 18 bases flanking the NNS codon. The polynucleotide sequencesof the forward and reverse primers used to mutate the amino acids atpositions 6, 30 and 32 are given in Table 1.

TABLE 1 Primer Bases Bases Name* Primer Sequence Left** Right***  6FGCTGCTGAAGAAGCAAAANNSAAATATT 18 22 TAATTGGCTTTAATG (SEQ ID NO: 26)  6RCATTAAAGCCAATTAAATATTTSNNTTTT 22 18 GCTTCTTCAGCAGC (SEQ ID NO: 27) 30FCAAGTAGAGGCAAATGACNNSGTCGCC 18 18 ATTCTCTCTGAG (SEQ ID NO: 28) 30RCTCAGAGAGAATGGCGACSNNGTCATT 18 18 TGCCTCTACTTG (SEQ ID NO: 29) 32FGAGGCAAATGACGAGGTCNNSATTCTC 18 18 TCTGAGGAAGAG (SEQ ID NO: 30) 32RCTCTTCCTCAGAGAGAATSNNGACCTCG 18 18 TCATTTGCCTC (SEQ ID NO: 31) *Theprimer names provided indicate the amino acid position at which thesubstitution is made; “R” indicates that the primer is the reverseprimer and “F” indicates that the primer is a forward primer. Forexample, 6F is the forward primer that was used in the substitution ofamino acid at position 6 of the pro sequence set forth in SEQ ID NO: 7.**“Bases left” and ***“Bases Right” indicate the number of bases to theleft and to the right of the mutating codon (“NNS”) that are present inthe primer. These bases are complementary to the bases of the templateprecursor polynucleotide bases.

pJH-P9 DNA was used as template in the QuikChange (QC) mutagenesisreaction as follows. Two microliters of pJH-P9 miniprep DNA (50 ng) wereadded to 40. μL of sterile distilled H₂O, 1 μL of PfuTurbo, 5 ul 10×Pfubuffer, 1 μL dNTPs (Roche), 0.5 μL of forward primer (5 uM), and 0.5 μlreverse primer (5 uM), for a total of 50 μL. The DNA amplificationreaction (PCR) was performed under the following cycling conditions: 95°C. for 1 min, once, followed by 19-20 cycles of 95° C. for 1 min., 55°C. for 1 min, and 68° C. for 12 min. Five microliters of the PCRreaction were analyzed by electrophoresis using a 1.2% E-gel(Invitrogen). Subsequently, the mutated amplified DNA was digestedtwice, using 1 μL DpnI at 37° C. for 2 to 8 hours. A negative controlwas generated under similar conditions, but in the absence of primers.One microliter of each of the DpnI-digested reaction products was usedto transform fifty microliters of one-shot TOP10 chemically competentcells (Invitrogen) using the manufacturer's protocol. The transformedcells were grown in Luria's Broth (LB) with shaking at 37 C for 1 hour,then streaked on Luria Agar (LA) plates containing 50 ppm carbenicillin,and allowed to grow at 37° C. overnight. Following the overnightincubation, individual colonies were picked, used to inoculate 150 μL ofLB containing 50 ppm carbenicillin, and grown overnight at 37° C. in96-well microtiter plates. An aliquot of the culture grown in the microtiter plates was transferred to LA plates containing 50 ppmcarbenicillin, and the plates were sent to Quintara Inc. for isolationand sequence analysis of the mutated DNA. Glycerol was added to a finalconcentration of 20% to the cultures remaining in the microtiter plates,which were then frozen at −80° C. and stored.

(b) Generation of B. Subtilis Strains Expressing Modified Pn Proteases.

Aliquots of the E. coli microtiter cell cultures harboring the mutatedpro sequences were used to inoculate 5 ml of LB+50 ppm carbenicillin.Plasmid DNA was prepared using a Qiagen kit (Qiagen), and a portion ofeach plasmid DNA was used to transform B. subtilis host cells. Tenmicroliters of the plasmid DNA (pJH-P9) were used to transform 100 ul ofB. subtilis comK competent cells (genotype: ΔaprE, ΔnprE, degUHy32,oppA, DspoIIE3501, amyE::xylRPxylAcomK-phleo). A control plasmidcontaining the P9 construct comprising the unmutated pro sequence(unmutated SEQ ID NO:7) was also transformed to B. subtilis comK cells.The transformed cells were incubated at 37° C. for 45 minutes whileshaking at 250 rpm. Cells from the transformation mixture were platedonto LA plates containing 1.6% skim milk and 5 ppm chloramphenicol (CMP)and incubated overnight in at 37° C. One colony, from each of thetransformations, was picked and re-streaked on the LA plates containing5 ppm CMP+1.6% skim milk.

Bacterial colonies harboring the control plasmid or a plasmid encoding amodified protease were used to inoculate 150 uL of Luria Brothcontaining 5 ppm CMP in wells of a microtiter plate. The microtiterplates were then incubated for four hours at 37° C. while rotating at250 rpm. 10 ul of each of the cultures were transferred to a newmicro-titer plate containing 140 ul of Grants II media, pH 7.3, and thecultures were grown in a shaking incubator at 37° C., 250 rpm for 40hours. (Grants II media was prepared as follows: Solution I: 10 g ofSoytone were dissolved in 500 ml water and autoclaved for 20-25 minutes;Solution II: 3 ml of 1M K2HPO4, 75 g glucose, 3.6 g urea, 100 ml Grant's10×MOPS were diluted into 400 ml water. Solutions I and II were mixedand the pH adjusted to pH7.3 with HCl/NaOH. The final volume wasadjusted to 1 L, and the final solution was sterilized through 0.22-umPES filter.) Following the incubation, the microtiter plates werecentrifuged and the supernatant of each of the cultures was assayed forprotease activity using the AAPF assay described below.

(c) Measurement of Modified Protease Production: AAPF Assay of ProteaseActivity

Each of the B. subtilis cultures obtained as described in Example 1(b),was assayed for the production of the modified proteases. The enzymesproduced were assayed for activity against the substrate, succinyl-L-Ala-L-Ala-L-Pro-L-Phe-p-nitroanalide (AAPF). The assay measured theproduction of modified protease as the increase in absorbance at 405nm/min resulting from the hydrolysis and release of p-nitroanaline(Estell et al., J Biol. Chem., 260:6518-6521 (1985)). The measurementswere made using the Softmax Pro software, and the specified conditionswere set as: Type: Kinetic; Reduction: Vmax Points (Read best 15/28points); Lm1: 405 nm; Time: 5 minutes; and Interval: 11 Seconds. Tenmicroliters of each of the B. subtilis cultures were diluted to 100 ulof Tris Buffer, containing 10 mM Tris+0.005% TWEEN®-80, pH 8.6; and 25ul of 100 mg/ml AAPF substrate to assay for protease activity. Therelative activity of each of the modified proteases was calculated, andthe effect of each amino acid substitution on the production of thecorresponding modified protease was determined as a ratio of theactivity of the mature protease processed from each modified protease tothe activity of the mature protease processed from the unmodifiedprotease precursor protease. Once the DNA construct was stablyintegrated into a competent Bacillus subtilis strain, the activity ofthe modified proteases was measured in microtiter assays and theactivity was compared to the activity of the corresponding proteaseprocessed from the unmodified precursor.

Ten microliters of overnight Grant II Media cell cultures were dilutedto 100 ul of Tris Buffer, containing 10 mM Tris+0.005% TWEEN®-80 pH 8.6;and 25 ul of 100 mg/ml AAPF substrate were used to assay for proteaseactivity. Assays were done in microtiter plates and the Softmax ProSoftware was used.

The results given in Tables 2, 3, and 4, showed that all but one of theamino acid substitutions of amino acids at positions 6 of the pro region(SEQ ID NO:7) within the precursor protease (SEQ ID NO:59) lead to anenhanced production of the mature form of the protease of SEQ ID NO:9,whereas all but one of the amino acid substitutions at positions 30 or32 showed similar or diminished protease production when compared to theproduction of the mature protease when processed from an unmodified proregion. In addition, site saturation of each of the substituted aminoacids showed that each amino acid can be substituted by two or moreamino acids at the same position to increase the production of themature form relative to that obtained from the precursor protease havingunmodified pro region.

TABLE 2 Effect of amino acid substitution at position 6 of the proregion on the production of the mature protease of SEQ ID NO: 9 Mutation(Substitution) at Percent activity relative to activity position in proregion from the unmodified precursor E6 (control) 100 E6A 119 E6R 236E6N 377 E6C 425 E6Q 455 E6G 458 E6H 117 E6M 280 E6F 411 E6P 529 E6S 512E6T 480 E6W 277 E6Y 7 E6V 550

TABLE 3 Effect of amino acid substitution at position 30 of the proregion on the production of the mature protease of SEQ ID NO: 9 Mutation(Substitution) at position in Percent activity relative to the proregion unmodified precursor E30 (control) 100 E30A 76 E30R 73 E30N 82E30D 80 E30G 47 E30H 78 E30I 61 E30L 66 E30M 75 E30F 70 E30P 69 E30S 73E30T 83 E30W 62 E30V 60

TABLE 4 Effect of amino acid substitution at position 32 of the proregion on the production of the mature protease of SEQ ID NO: 9 Mutation(Substitution) at positions in Percent activity relative to activity proregion from the unmodified precursor A32 (control) 100 A32R 64 A32N 76A32Q 75 A32E 46 A32G 78 A32H 60 A32I 67 A32L 76 A32K 121 A32F 32 A32P 37A32S 74 A32T 99 A32W 80 A32V 98(d) Site-Saturation Mutagenesis: Generation of Combinations ofSubstitutions in the Pro Region

The plasmid expressing the A32K substitution in the pro region (SEQ IDNO:7) comprised in the full-length protease of SEQ ID NO:59 wassubjected to a second round of site-saturation mutagenesis of the codonat position 6 to create a first library of polynucleotides that encode afull-length protease containing a substitution of amino acid 6 incombination with the A32K substitution of the pro region of theprotease. The mutation at position 6 was created using the QuikChange®site-directed mutagenesis kit (QC; Stratagene) according to thedirections provided by the manufacturer using forward and reverseprimers of SEQ ID NOS:26 and 27, respectively. Similarly, a secondlibrary of polynucleotides was created to encode a full-length proteasecontaining a substitution of amino acid 30 in combination with the A32Ksubstitution in the pro region of the protease was created. Thecomplementary overlapping forward(CAAGTAGAGGCAAATGACNNSGTCAAAATTCTCTCTGAG; SEQ ID NO:32) and reverseprimers (CTCAGAGAGAATTTTGACSNNGTCATTTGCCTCTACTTG; SEQ ID NO:33) wereused for mutating the position 30.

The QC reaction, amplification of the plasmid DNA, and transformation ofE. coli cells were performed as described in Example 1(a). Thesubsequent transformation of Bacillus subtilis competent cells was alsoperformed as described in Example 1(b). Supernatants from Bacilluscultures expressing proteases from modified or unmodified precursor wereanalyzed for protease activity using the AAPF assay as described inExample 1(c).

Results shown in Tables 5 and 6 indicate that most substitutions of theamino acid at position 6 (Table 5) of the pro region when in combinationwith the substitution A32K further enhance the production of the matureform of the protease expressed from a polynucleotide encoding anunmodified pro region or a pro region containing the A32K substitution.However, the combination of amino acid substitutions at position 30 whenin combination with the A32K substitution did not enhance the productionof the mature protease of SEQ ID NO:9 (Table 6).

TABLE 5 Effect of the combination of amino acid substitution A32K withsubstitutions of amino acid at position 6 of the pro region on theproduction of mature protease of SEQ ID NO: 9 Mutation (Substitution) atPercent activity relative to activity from positions in pro region themodified precursor E6-A32K E6-A32K (control, modified) 100 E6R-A32K 160E6N-A32K 120 E6D-A32K 170 E6C-A32K 71 E6G-A32K 79 E6I-A32K 103 E6L-A32K50 E6K-A32K 132 E6M-A32K 127 E6F-A32K 71 E6P-A32K 161 E6S-A32K 82E6T-A32K 134 E6W-A32K 60 E6Y-A32K 95 E6V-A32K 63

TABLE 6 Effect of the combination of amino acid substitution A32K withsubstitutions of amino acid at position 30 of the pro region on theproduction of mature protease of SEQ ID NO: 9 Mutation (substitution) atPercent activity relative to activity from positions in pro region themodified precursor E30-A32K E30-A32K (control, modified) 100 E30A-A32K38 E30R-A32K 33 E30N-A32K 33 E30D-A32K 34 E30C-A32K 33 E30Q-A32K 33E30G-A32K 38 E30H-A32K 40 E30I-A32K 30 E30L-A32K 33 E30K-A32K 47E30M-A32K 45 E30F-A32K 36 E30P-A32K 72 E30S-A32K 67 E30T-A32K 26E30W-A32K 85 E30Y-A32K 96 E30V-A32K 65(e) Effect of Amino Acid Substitution(s) in the Pro Region of thePrecursor Protease on the Production of the Mature Protease of SEQ IDNO:9 in Shake Flask Cultures.

To test the effect of amino acid substitutions in the pro region on theproduction of the mature protease of SEQ ID NO:9 in shake flaskcultures, several of the Bacillus subtilis strains grown in themicrotiter plates as described above were grown as follows. Bacillussubtilis strains expressing the modified precursor comprising a singlesubstitution at one of positions 6, 30 and 32 of the pro region, orcomprising a combination of two substitutions of amino acids atpositions 6 and 32, or 30 and 32 of the pro region and that werepreviously grown in microtiter plates, were first plated on Luria Agarplates containing 5 ppm chloramphenicol and 1.6% skim milk. A singlecolony was used to inoculate 5 ml of Luria Broth containing 5 ppmchloramphenicol. Each 5 ml culture was grown for 5 hours at 37° C. whileshaking at 250 rpm. A 250 ml shake flask containing 25 ml of Grant's IImedia was inoculated with 1 ml of the 5 ml culture of strains comprisinga single substitution, and the 250 ml culture was incubated for 40, at37° C. while shaking at 250 rpm. Strains comprising double substitutionswere grown for 40 and/or for 48 hours, as shown by the data given inTables 9 and 10. Supernatant from the shake flask cultures was assayedfor AAPF activity as described in Example 1(c). The results for theactivity in strains comprising a single substitution are shown in Tables7 and 8, and the results for the activity in strains comprising asubstitution at position 6 or 32 in combination with the A32Ksubstitution are shown in Tables 9 and 10, respectively.

The results show that the enhancement of protease production obtainedfrom modified precursor proteases in microtiter cultures is mimicked inmost shake flask cultures. Eight of 22 strains did not mirror theproduction of protease in shake flask that was seen in microtiterplates. Four of the eight strains, which produced more protease thantheir respective controls when grown in microtiter plates produced lessprotease than the respective controls when grown in shake flasks (E6C,E6F, E6D-A32K and E6K-A32K). The remaining four strains, which producedless protease than their respective controls when grown in microtiterplates produced more protease than the respective controls when grown inshake flasks (A32T, A32V, E6S-A32K, E30V-A32K, and E30W-A32K). It islikely that the production of protease by these strains is affected bythe different growth conditions imposed in microtiter versus shake flaskcultures. One skilled in the art would know how to optimize growthconditions.

TABLE 7 Effect of amino acid substitution at position 6 of the proregion on the production of the mature protease of SEQ ID NO: 9 in shakeflask cultures Mutation (substitution) at Percent activity relative toactivity from position in pro region the unmodified precursor (48 hours)E6 (control) 100 E6N 111 E6C 84 E6Q 149 E6G 140 E6F 91 E6P 110 E6S 114E6T 113 E6V 145

TABLE 8 Effect of amino acid substitution at position 32 of the proregion of the mature protease of SEQ ID NO: 9 in shake flask culturesMutation (substitution) at Percent activity relative to activity frompositions in pro region the unmodified precursor (48 hours) A32(control) 100 A32K 140 A32T 260 A32V 190

TABLE 9 Effect of the combination of amino acid substitution A32K withsubstitutions of amino acid at position 6 of the pro region of themature protease of SEQ ID NO: 9 in shake flask cultures Percent activityrelative to activity Mutation (substitution) from the modified precursorA32K at positions in pro region 40 hours 48 hours E6-A32K (control, 100100 modified) E6R-A32K 108 126 E6N-A32K 91 110 E6D-A32K 64 80 E6K-A32K59 65 E6M-A32K 126 179 E6S-A32K 77 106

TABLE 10 Effect of the combination of amino acid substitution A32K withsubstitutions of amino acid at position 30 of the pro region of themature protease of SEQ ID NO: 9 in shake flask cultures Percent activityrelative to activity Mutation (substitution) at positions from themodified precursor A32K in pro region of GG36 precursor 40 hours 48hours E30-A32K (control, modified) 100 100 E30P-A32K 73 86 E30W-A32K 13093 E30Y-A32K 90 99 E30V-A32K 92 132

EXAMPLE 2 The Effect of Mutations in the Pro Region of SEQ ID NO:7 onthe Production of the Mature Alkaline Protease of SEQ ID NO:11

Site-Saturation Mutagenesis of Amino Acids at Positions 6, 30 or 32 ofthe Pro Region

Site-saturation mutagenesis of the pro region on the production of themature protease of SEQ ID NO:11 was performed using the QuikChange®site-directed mutagenesis kit (QC; Stratagene) according to thedirections of the manufacturer. A DNA cassette comprising the AprEpromoter, and the polynucleotide that encodes the full-length proteaseof SEQ ID NO:60 was cloned into the EcoRI and HindIII restriction sitesof the pJH101 vector (Ferrari et al. J. Bacteriol. 154:1513-1515 [1983])pJH-Pn (FIG. 4A) to generate the pJH-P11 plasmid. (Pn refers to the SEQID NO of the mature protease that is expressed from the pJH-Pn plasmid).The DNA cassette comprised the B. subtilis aprE promotergaattcctccattttcttctgctatcaaaataacagactcgtgattttccaaacgagctttcaaaaaagcctctgccccttgcaaatcggatgcctgtctataaaattcccgatattggttaaacagcggcgcaatggcggccgcatctgatgtctttgcttggcgaatgttcatcttatttcttcctccctctcaataattUttcattctatccatttctgtaaagtttatttttcagaatacttttatcatcatgctttgaaaaaatatcacgataatatccattgttctcacggaagcacacgcaggtcatttgaacgaattUttcgacaggaatttgccgggactcaggagcatttaacctaaaaaagcatgacatttcagcataatgaacatttactcatgtctattttcgttcttttctgtatgaaaatagttatttcgagtctctacggaaatagcgagagatgatatacctaaatagagataaaatcatctcaaaaaaatgggtctactaaaatattattccatctattacaataaattcacagaatagtatttaagtaagtctactctgaatttttttaaaaggagagggtaaaga (SEQID NO:1),

the polynucleotide sequencegtgagaagcaaaaaattgtggatcagcttgttgtttgcgttaacgttaatctttacgatggcgttcagcaacatgtctgcgcaggct(SEQ ID NO:2), which encodes the AprE signal peptideVRSKKLWISLLFALTLIFTMAFSNMSAQA (SEQ ID NO:3),

the polynucleotide sequencegctgaagaagcaaaagaaaaatatttaattggctttaatgagcaggaagctgtcagtgagtttgtagaacaagtagaggcaaatgacgaggtcgccattctctctgaggaagaggaagtcgaaattgaattgcttcatgaatttgaaacgattcctgUttatccgttgagttaagcccagaagatgtggacgcgcttgaactcgatccagcgatttcttatattgaagaggatgcagaagtaacgacaatg(SEQ ID NO:6)which encodes the unmodified pro regionAEEAKEKYLIGFNEQEAVSEFVEQVEANDEVAILSEEEEVEIELLHEFETIPVLSVELSPEDVDALELDPAISYIEEDAEVTTM (SEQ ID NO:7), and the polynucleotide sequencegcgcaatcagtgccatggggaattagccgtgtgcaagccccagctgcccataaccgtggattgacaggttctggtgtaaaagttgctgtcctcgatacaggtatttccactcatccagacttaaatattcgtggtggcgctagctttgtaccaggggaaccatccactcaagatgggaatgggcatggcacgcatgtggccgggacgattgctgctctagacaattcgattggcgttcttggcgtagcgccgagcgcggaactatacgctgttaaagtattaggggcgagcggttcaggcgccatcagctcgattgcccaaggattggaatgggcagggaacaatggcatgcacgttgctaatttgagtttaggaagcccttcgccaagtgccacacttgagcaagctgttaatagcgcgacttctagaggcgttcttgttgtagcggcatctggaaattcaggtgcaggctcaatcagctatccggcccgttatgcgaacgcaatggcagtcggagctactgaccaaaacaacaaccgcgccagcttttcacagtatggcgcagggcttgacattgtcgcaccaggtgtaaacgtgcagagcacatacccaggttcaacgtatgccagcttaaacggtacatcgatggctactcctcatgttgcaggtgcagcagcccttgttaaacaaaagaacccatcttggtccaatgtacaaatccgcaatcatctaaagaatacggcaacgagcttaggaagcacgaacttgtatggaagcggacttgtcaatgcagaagctgcaactcgt(SEQ ID NO:10), which encodes the mature region of protease P11 (SEQ IDNO:11) AQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALDNSIGVLGVAPSAELYAVKVLGASGSGAISSIAQGLEWAGNNGMHVANLSLGSPSPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR (SEQ ID NO:11).

Each of the 3 codons in the pro region of SEQ ID NO:7, exemplified byNNG/C, comprised in the full-length protease of SEQ ID NO:60, weremutated to be substituted by the 32 possible nucleotide triplets thatencode the 20 naturally occurring amino acids to generate threelibraries as follows. An aliquot of plasmid pJH-P11 DNA comprising thesequence encoding the full-length protease was mutated to generate afirst library of clones encoding all possible substitutions of glutamicacid (E) at position 6 (E6X) of the pro region (SEQ ID NO:7); a secondaliquot was mutated to generate a second library of clones encoding allpossible substitutions of glutamic acid (E) at position 30 (E30X) of thepro region (SEQ ID NO:7); and a third aliquot was mutated to generate athird library of clones encoding all possible substitutions of arginine(A) at position 32 (A32X) of the pro region (SEQ ID NO:7). Complementaryoverlapping primers were designed for mutating the codons of interestwith about 18 bases flanking the NNS codon. The polynucleotide sequencesof the forward and reverse primers used to mutate the amino acids atpositions 6, 30 and 32 are given in Table 1.

The QC reaction, amplification of the plasmid DNA, and transformation ofE. coli cells were performed as described in Example 1(a). Thesubsequent transformation of Bacillus subtilis competent cells was alsoperformed as described in Example 1(b). Supernatants from Bacilluscultures expressing proteases from modified or unmodified precursor wereanalyzed for protease activity using the AAPF assay as described inExample 1(c).

The results given in Tables 11, 12, and 13, show that most amino acidsubstitutions of amino acids at positions 6, 30 and 32 of the pro region(SEQ ID NO:7) in the precursor protease (SEQ ID NO:60) lead to anenhanced production of the mature form of the protease. In addition,site saturation of each of the substituted amino acids showed that eachamino acid can be substituted by two or more amino acids at the sameposition to increase the production of the mature form relative to thatobtained from the precursor protease having unmodified pro region.

TABLE 11 Effect of amino acid substitution at position 6 of the proregion on the production of the mature protease of SEQ ID NO: 11Mutation (Substitution) at position in Percent activity relative toactivity pro region from the unmodified precursor E6 (control) 100 E6A125 E6R 120 E6Q 161 E6G 187 E6L 177 E6K 160 E6M 165 E6F 131 E6P 72 E6S56 E6T 103 E6W 52 E6V 265

TABLE 12 Effect of amino acid substitution at position 30 of the proregion on the production of the mature protease of SEQ ID NO: 11Mutation (Substitution) at position in Percent activity relative toactivity pro region from the unmodified precursor E30 (control) 100 E30A90 E30R 112 E30N 97 E30Q 126 E30G 111 E30I 132 E30L 128 E30M 152 E30F102 E30P 132 E30T 125 E30W 105 E30Y 125 E30V 142

TABLE 13 Effect of amino acid substitution at position 32 of the proregion on the production of the mature protease of SEQ ID NO: 11Mutation (Substitution) at position in Percent activity relative toactivity pro region from the unmodified precursor A30 (control) 100 A32R99 A32D 98 A32C 100 A32Q 11 A32G 96 A32H 98 A32L 98 A32M 98 A32F 93 A32P93 A32S 117 A32T 129 A32V 124

Effect of Amino Acid Substitution(s) in the Pro Region of the PrecursorProtease on the Production of the Mature Protease of SEQ ID NO:11 inShake Flask Cultures

To test the effect of amino acid substitutions in the pro region on theproduction of the mature protease of SEQ ID NO:11 in shake flaskcultures, several of the Bacillus subtilis strains comprising asubstitution at position 6 of the pro region in the precursor proteaseas described above were grown for 48 hours as described in Example 1(e).Supernatant from the shake flask cultures was assayed for AAPF activityas described in Example 1(c).

The results shown in Table 14 indicate that substitutions made atposition 6 of the P11 precursor sequence which were shown to enhance theproduction of the mature protease (SEQ ID NO:11) in cultures grown inmicrotiter plates also increase the production of the protease incultures grown in shake flasks.

TABLE 14 Effect of amino acid substitutions at position 6 of the proregion on the production of the mature protease of SEQ ID NO: 11 inshake flask cultures Mutation (substitution) at Percent activityrelative to activity from the position in pro region unmodifiedprecursor (48 hours) E6 (control) 100 E6A 157 E6R 137 E6Q 82 E6G 88 E6L130 E6K 121 E6M 99 E6F 43 E6V 116

EXAMPLE 3 The Effect of Mutations in the Pro Region of SEQ ID NO:7 onthe Production of the Mature Alkaline Protease of SEQ ID NO:19

(a) Site-Saturation Mutagenesis of Amino Acids at Positions 6, 30 or 32of the Pro Region

Site-saturation mutagenesis of the pro region on the production of themature protease of SEQ ID NO:19 was performed using the QuikChange®site-directed mutagenesis kit (QC; Stratagene) according to thedirections of the manufacturer. A DNA cassette comprising the AprEpromoter, and the polynucleotide that encodes the full-length proteaseof SEQ ID NO:64 was cloned into the EcoRI and HindIII restriction sitesof the pJH101 vector (Ferrari et al. J. Bacteriol. 154:1513-1515 [1983])pJH-Pn (FIG. 4A) to generate the pJH-P19 plasmid. (Pn refers to the SEQID NO of the mature protease that is expressed from the pJH-Pn plasmid).The DNA cassette comprised the B. subtilis aprE promotergaattcctccattttcttctgctatcaaaataacagactcgtgattttccaaacgagctttcaaaaaagcctctgccccttgcaaatcggatgcctgtctataaaattcccgatattggttaaacagcggcgcaatggcggccgcatctgatgtctttgcttggcgaatgttcatcttatttcttcctccctctcaataattUttcattctatccatttctgtaaagtttatttttcagaatacttttatcatcatgctttgaaaaaatatcacgataatatccattgttctcacggaagcacacgcaggtcatttgaacgaattllttcgacaggaatttgccgggactcaggagcatttaacctaaaaaagcatgacatttcagcataatgaacatttactcatgtctattttcgttcttttctgtatgaaaatagttatttcgagtctctacggaaatagcgagagatgatatacctaaatagagataaaatcatctcaaaaaaatgggtctactaaaatattattccatctattacaataaattcacagaatagtcffitaagtaagtctactctgaattffittaaaaggagagggtaaaga (SEQID NO:1),

the polynucleotide sequencegtgagaagcaaaaaattgtggatcagcttgttgffigcgttaacgttaatattacgatggcgttcagcaacatgtctgcgcaggct(SEQ ID NO:2), which encodes the AprE signal peptideVRSKKLWISLLFALTLIFTMAFSNMSAQA (SEQ ID NO:3),

the polynucleotide sequencegctgaagaagcaaaagaaaaatatttaattggctttaatgagcaggaagctgtcagtgagffigtagaacaagtagaggcaaatgacgaggtcgccattctctctgaggaagaggaagtcgaaattgaattgcttcatgaatttgaaacgattcctgffitatccgttgagttaagcccagaagatgtggacgcgcttgaactcgatccagcgafficttatattgaagaggatgcagaagtaacgacaatg(SEQ ID NO:6),which encodes the unmodified pro region AEEAKEKYLI GFNEQEAVSE FVEQVEANDEVAILSEEEEV EIELLHEFET IPVLSVELSP EDVDALELDP AISYIEEDAEVTTM (SEQ IDNO:7), and the polynucleotide sequencegcgcaatcggtaccatggggaattagccgtgtgcaagccccagctgcccataaccgtggattgacaggttctggtgtaaaagttgctgtcctcgatacaggtafficcactcatccagacttaaatattcgtggtggcgctagtffigtaccaggggaaccatccactcaagatgggaatgggcatggcacgcatgtggctgggacgattgctgctttaaacaattcgattggcgttcttggcgtagcaccgaacgcggaactatacgctgttaaagtattaggggcgagcggtggcggttcgaacagctcgattgcccaaggattggaatgggcagggaacaatggcatgcacgttgctaatttgagtttaggaagcccttcgccaagtgccacacttgagcaagctgttaatagcgcgacttctagaggcgttcttgttgtagcggcatctggcaattcaggtgcaggctcaatcagctatccggcccgttatgcgaacgcaatggcagtcggagctactgaccaaaacaacaaccgcgccagctfficacagtatggcgcagggcttgacattgtcgcaccaggtgtaaacgtgcagagcacatacccaggttcaacgtatgccagcttaaacggtacatcgatggctactcctcatgttgcaggtgcagcagcccttgttaaacaaaagaacccatcttggtccaatgtacaaatccgcaatcatctaaagaatacggcaacgagcttaggaagcacgaacttgtatggaagcggacttgtcaatgcagaagcggcaacacgt(SEQ ID NO:18) encoding mature region of protease 19 (P19) (SEQ IDNO:19) AQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALNNSIGVLGVAPNAELYAVKVLGASGGGSNSSIAQGLEWAGNNGMHVANLSLGSPSPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR (SEQ ID NO:19).

Two codons in the pro region of SEQ ID NO:7, exemplified by NNG/C,comprised in the full-length protease of SEQ ID NO:64, were mutated tobe substituted by the 32 possible nucleotide triplets that encode the 20naturally occurring amino acids to generate two libraries as follows. Analiquot of plasmid pJH-P19 DNA comprising the sequence encoding thefull-length protease was mutated to generate a first library of clonesencoding all possible substitutions of glutamic acid (E) at position 6(E6X) of the pro region (SEQ ID NO:7); and a second aliquot was mutatedto generate a second library of clones encoding all possiblesubstitutions of arginine (A) at position 32 (A32X) of the pro region(SEQ ID NO:7). Complementary overlapping primers were designed formutating the codons of interest with about 18 bases flanking the NNScodon. The polynucleotide sequences of the forward and reverse primersused to mutate the amino acids at positions 6 and 32 are given in Table1.

The QC reaction, amplification of the plasmid DNA, and transformation ofE. coli cells were performed as described in Example 1(a). Thesubsequent transformation of Bacillus subtilis competent cells was alsoperformed as described in Example 1(b). Supernatants from Bacilluscultures expressing proteases from modified or unmodified precursor wereanalyzed for protease activity using the AAPF assay as described inExample 1(c).

The results given in Tables 15 and 16 show that amino acid substitutionof most of the amino acids of the precursor protease lead to an enhancedproduction of the mature form of the protease. In addition, sitesaturation of each of the substituted amino acids showed that each aminoacid can be substituted by two or more amino acids at the same positionto increase the production of the mature form relative to that obtainedfrom the precursor protease having unmodified pro region.

TABLE 15 Effect of amino acid substitution at position 6 of the proregion on the production of the mature protease of SEQ ID NO: 19Mutation (Substitution) at position in Percent activity relative toactivity pro region from the unmodified precursor E6 (control) 100 E6A128 E6C 25 E6D 53 E6G 95 E6H 133 E6I 36 E6K 111 E6L 50 E6N 35 E6P 28 E6Q45 E6R 100 E6S 71 E6W 31 E6T 75

TABLE 16 Effect of amino acid substitution at position 30 of the proregion on the production of the mature protease of SEQ ID NO: 19Mutation (Substitution) at position in Percent activity relative toactivity pro region from the unmodified precursor E30 (control) 100 E30A488 E30R 384 E30N 405 E30D 241 E30G 374 E30H 371 E30I 51 E30L 211 E30K265 E30F 168 E30P 66 E30S 601 E30T 351 E30V 254(b) Site-Saturation Mutagenesis: Generation of Combinations ofSubstitutions in the Pro Region.

The plasmid expressing the E30G substitution in the pro region (SEQ IDNO:7) comprised in the full-length protease of SEQ ID NO:64 wassubjected to a second round of site-saturation mutagenesis of the codonat position 6 to create a library of polynucleotides that encode afull-length protease containing a substitution of amino acid 6 incombination with the E30G substitution of the pro region of theprotease. The mutation at position 6 was created using the QuikChange®site-directed mutagenesis kit (QC; Stratagene) according to thedirections provided by the manufacturer using forward and reverseprimers of SEQ ID NOS:26 and 27, respectively.

The QC reaction, amplification of the plasmid DNA, and transformation ofE. coli cells were performed as described in Example 1(a). Thesubsequent transformation of Bacillus subtilis competent cells was alsoperformed as described in Example 1(b). Supernatants from Bacilluscultures expressing proteases from modified or unmodified precursor wereanalyzed for protease activity using the AAPF assay as described inExample 1(c).

Results shown in Table 17 indicate that most substitutions of amino acidat position 6 of the pro region when in combination with thesubstitution E30G at amino acid position 30 lead to an enhancedproduction of the mature form of the protease.

TABLE 17 Effect of the combination of amino acid substitution E30G withsubstitutions of amino acid at position 6 of the pro region on theproduction of mature protease of SEQ ID NO: 19 Mutation (Substitution)at positions in pro Percent activity relative to activity from region ofprecursor E6X-E30G the unmodified precursor E6-E30 E6-E30 (control,unmodified) 100 E6A-E30G 188 E6R-E30G 126 E6N-E30G 158 E6D-E30G 126E6C-E30G 220 E6Q-E30G 147 E6G-E30G 107 E6H-E30G 144 E6L-E30G 96 E6K-E30G117 E6M-E30G 114 E6F-E30G 152 E6P-E30G 108 E6S-E30G 108 E6T-E30G 100E6W-E30G 104 E6V-E30G 185 E6Y-E30G 148(c) Effect of Amino Acid Substitution(s) in the Pro Region of thePrecursor Protease on the Production of the Mature Protease of SEQ IDNO:19 in Shake Flask Cultures.

To test the effect of amino acid substitutions in the pro region on theproduction of the mature protease of SEQ ID NO:19 in shake flaskcultures, several of the Bacillus subtilis strains grown in themicrotiter plates as described above and containing the combinations ofsubstitutions E6A-E30G, E6C-E30G, and E6V-E30G in the pro region weregrown for 48 hours as described in Example 1(e). Supernatant from theshake flask cultures was assayed for AAPF activity as described inExample 1(c).

The results shown in Table 18 indicate that the combination of mutationsE6A and E30G in the pro region of the protease precursor leads toenhanced production of the mature protease (SEQ ID NO:19) compared tothe production of the protease processed from the precursor containingthe single mutation E30G.

TABLE 18 Effect of the combination of amino acid substitution E30G withsubstitutions of amino acid at position 6 of the pro region of themature protease of SEQ ID NO: 19 in shake flask cultures Percentactivity relative to Mutation (substitution) at activity from themodified precursor positions in modified pro region E30G (48 hours) E6-E30G 100 E6A-E30G 178 E6C-E30G 97 E6V-E30G 92

EXAMPLE 4 The Effect of Mutations in the Pro Region of SEQ ID NO:7 onthe Production of the Mature Alkaline Protease of SEQ ID NO:17

Site-Saturation Mutagenesis of Amino Acids at Positions 6, 30 or 32 ofthe Pro Region

Site-saturation mutagenesis of the pro region on the production of themature protease of SEQ ID NO:17 was performed using the QuikChange®site-directed mutagenesis kit (QC; Stratagene) according to thedirections of the manufacturer. A DNA cassette comprising the AprEpromoter, and the polynucleotide that encodes the full-length proteaseof SEQ ID NO:63 was cloned into the EcoRI and HindIII restriction sitesof the pJH101 vector (Ferrari et al. J. Bacteriol. 154:1513-1515 [1983])pJH-Pn (FIG. 4A) to generate the pJH-P17 plasmid. (Pn refers to the SEQID NO of the mature protease that is expressed from the pJH-Pn plasmid).The DNA cassette comprised the B. subtilis aprE promotergaattcctccattttcttctgctatcaaaataacagactcgtgattttccaaacgagctttcaaaaaagcctctgccccttgcaaatcggatgcctgtctataaaattcccgatattggttaaacagcggcgcaatggcggccgcatctgatgtctttgcttggcgaatgttcatcttatttcttcctccctctcaataattUttcattctatccatttctgtaaagtttatttttcagaatacttttatcatcatgctttgaaaaaatatcacgataatatccattgttctcacggaagcacacgcaggtcatttgaacgaattUttcgacaggaatttgccgggactcaggagcatttaacctaaaaaagcatgacatttcagcataatgaacatttactcatgtctattttcgttcttttctgtatgaaaatagttatttcgagtctctacggaaatagcgagagatgatatacctaaatagagataaaatcatctcaaaaaaatgggtctactaaaatattattccatctattacaataaattcacagaatagtatttaagtaagtctactctgaatttttttaaaaggagagggtaaaga (SEQID NO:1), the polynucleotide sequencegtgagaagcaaaaaattgtggatcagcttgttgtttgcgttaacgttaatctttacgatggcgttcagcaacatgtctgcgcaggct(SEQ ID NO:2), which encodes the AprE signal peptideVRSKKLWISLLFALTLIFTMAFSNMSAQA (SEQ ID NO:3),

the polynucleotide sequencegctgaagaagcaaaagaaaaatatttaattggctttaatgagcaggaagctgtcagtgagtttgtagaacaagtagaggcaaatgacgaggtcgccattctctctgaggaagaggaagtcgaaattgaattgcttcatgaatttgaaacgattcctgttttatccgttgagttaagcccagaagatgtggacgcgcttgaactcgatccagcgatttcttatattgaagaggatgcagaagtaacgacaatg(SEQ ID NO:6), which encodes the unmodified pro regionAEEAKEKYLIGFNEQEAVSEFVEQVEANDEVAILSEEEEVEIELLHEFETIPVLSVELSPEDVDALELDPAISYIEEDAEVTTM (SEQ ID NO:7), and the polynucleotide sequenceGCGCAATCGGTACCATGGGGAATTAGCCGTGTGCAAGCCCCAGCTGCCCATAACCGTGGATTGACAGGTTCTGGTGTAAAAGTTGCTGTCCTCGATACAGGTATTTCCACTCATCCAGACTTAAATATTCGTGGTGGCGCTAGCTTTGTACCAGGGGAACCATCCACTCAAGATGGGAATGGGCATGGCACGCATGTGGCTGGGACGATTGCTGCTTTAAACAATTCGATTGGCGTTCTTGGCGTAGCACCGAACGCGGAACTATACGCTGTTAAAGTATTAGGGGCGAGCGGTATGGGTTCGGTCAGCTCGATTGCCCAAGGATTGGAATGGGCAGGGAACAATGTTATGCACGTTGCTAATTTGAGTTTAGGACTGCAGGCACCAAGTGCCACACTTGAGCAAGCTGTTAATAGCGCGACTTCTAGAGGCGTTCTTGTTGTAGCGGCATCTGGCAATTCAGGTGCAGGCTCAATCAGCTATCCGGCCCGTTATGCGAACGCAATGGCAGTCGGAGCTACTGACCAAAACAACAACCGCGCCAGCTTTTCACAGTATGGCGCAGGGCTTGACATTGTCGCACCAGGTGTAAACGTGCAGAGCACATACCCAGGTTCAACGTATGCCAGCTTAAACGGTACATCGATGGCTACTCCTCATGTTGCAGGTGCAGCAGCCCTTGTTAAACAAAAGAACCCATCTTGGTCCAATGTACAAATCCGCAATCATCTAAAGAATACGGCAACGAGCTTAGGAAGCACGAACTTGTATGGAAGCGGACTTGTCAATGCAGAAGCGGCAACACGT (SEQ ID NO:16),which encodes the mature region of protease 17 (P17)AQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALNNSIGVLGVAPNAELYAVKVLGASGMGSVSSIAQGLEWAGNNVMHVANLSLGLQAPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR (SEQ ID NO:17).

Each of the 3 codons in the pro region of SEQ ID NO:7, exemplified byNNG/C, comprised in the full-length protease of SEQ ID NO:63, weremutated to be substituted by the 32 possible nucleotide triplets thatencode the 20 naturally occurring amino acids to generate threelibraries as follows. An aliquot of plasmid pJH-P17 DNA comprising thesequence encoding the full-length protease was mutated to generate afirst library of clones encoding all possible substitutions of glutamicacid (E) at position 6 (E6X) of the pro region (SEQ ID NO:7); a secondaliquot was mutated to generate a second library of clones encoding allpossible substitutions of glutamic acid (E) at position 30 (E30X) of thepro region (SEQ ID NO:7); and a third aliquot was mutated to generate athird library of clones encoding all possible substitutions of arginine(A) at position 32 (A32X) of the pro region (SEQ ID NO:7). Complementaryoverlapping primers were designed for mutating the codons of interestwith about 18 bases flanking the NNS codon. The polynucleotide sequencesof the forward and reverse primers used to mutate the amino acids atpositions 6, 30 and 32 are given in Table 1.

The QC reaction, amplification of the plasmid DNA, and transformation ofE. coli cells were performed as described in Example 1(a). Thesubsequent transformation of Bacillus subtilis competent cells was alsoperformed as described in Example 1(b). Supernatants from Bacilluscultures expressing proteases from modified or unmodified precursor wereanalyzed for protease activity using the AAPF assay as described inExample 1(c).

The results given in Tables 19, 20 and 21 show that most of the aminoacid substitutions of amino acids at positions 6, 30 or 32 of the proregion of the P17 precursor protease lead to an enhanced production ofthe mature form of the protease (SEQ ID NO:17). In addition, sitesaturation of each of the substituted amino acids showed that each aminoacid can be substituted by two or more amino acids at the same positionto increase the production of the mature form relative to that obtainedfrom the precursor protease having unmodified pro region.

TABLE 19 Effect of amino acid substitution at position 6 of the proregion on the production of the mature protease of SEQ ID NO: 17Mutation (Substitution) at Percent activity relative to activityposition in pro region from the unmodified precursor E6 (control) 100E6A 152 E6R 231 E6C 172 E6Q 229 E6G 95 E6H 144 E6I 106 E6L 76 E6K 269E6M 124 E6F 55 E6P 20 E6S 154 E6T 34 E6W 48 E6Y 114 E6V 55

TABLE 20 Effect of amino acid substitution at position 30 of the proregion on the production of the mature protease of SEQ ID NO: 17Mutation (Substitution) at Percent activity relative to activityposition in pro region from the unmodified precursor E30 (control) 100E30A 190 E30R 152 E30N 122 E30D 106 E30C 89 E30Q 128 E30G 223 E30H 83E30I 78 E30L 112 E30M 137 E30P 129 E30S 159 E30T 176 E30W 243 E30Y 130E30V 131

TABLE 21 Effect of amino acid substitution at position 32 of the proregion on the production of the mature protease of SEQ ID NO: 17Mutation (Substitution) at Percent activity relative to activityposition in pro region from the unmodified precursor A32 (control) 100A32R 142 A32D 81 A32C 170 A32Q 53 A32E 100 A32G 139 A32L 145 A32K 216A32F 137 A32P 50 A32S 81 A32T 154 A32Y 277 A32V 146(b) Site-Saturation Mutagenesis: Generation of Combinations of TwoSubstitutions in the Pro Region.

The plasmid expressing the E30G substitution in the pro region (SEQ IDNO:7) comprised in the full-length protease of SEQ ID NO:63 wassubjected to a second round of site-saturation mutagenesis of the codonat position 6 to create a first library of polynucleotides that encode afull-length protease containing a substitution of amino acid 6 incombination with the E30G substitution of the pro region of theprotease. The mutation at position 6 was created using the QuikChange®site-directed mutagenesis kit (QC; Stratagene) according to thedirections provided by the manufacturer using forward and reverseprimers of SEQ ID NOS:26 and 27, respectively. Similarly, a secondlibrary of polynucleotides was created to encode a full-length proteasecontaining a substitution of amino acid 32 in combination with the E30Gsubstitution in the pro region of the protease was created. Thecomplementary overlapping forwardGAGGCAAATGACGGCGTCNNSATTCTCTCTGAGGAAGAG (SEQ ID NO:34) and reverseprimers CTCTTCCTCAGAGAGAATSNNGACGCCGTCATTTGCCTC (SEQ ID NO:35), wereused for mutating the position 32.

The QC reaction, amplification of the plasmid DNA, and transformation ofE. coli cells were performed as described in Example 1(a). Thesubsequent transformation of Bacillus subtilis competent cells was alsoperformed as described in Example 1(b). Supernatants from Bacilluscultures expressing proteases from modified or unmodified precursor wereanalyzed for protease activity using the AAPF assay as described inExample 1(c).

Results shown in Tables 22 and 23 indicate that most substitutions ofthe amino acid at position 6 (Table 22) of the pro region of P17 when incombination with the substitution E30G further enhance the production ofthe mature form of the protease expressed from a polynucleotide encodingan unmodified pro region or a pro region containing the E30Gsubstitution. Similarly, the results shown in Table 23 show that thecombination of the E30G substitution with several substitutions atposition 32 also further enhanced the production of the mature form ofthe protease expressed from a polynucleotide encoding an unmodified proregion or a pro region containing the E30G substitution.

TABLE 22 Effect of the combination of amino acid substitution E30G withsubstitutions of amino acid at position 6 of the pro region on theproduction of mature protease of SEQ ID NO: 17 Mutation (Substitution)at Percent activity relative to activity from the positions in proregion modified precursor E30G E30G (control) 100 E6A-E30G 106 E6R-E30G136 E6C-E30G 157 E6Q-E30G 107 E6G-E30G 180 E6H-E30G 134 E6L-E30G 50E6K-E30G 153 E6M-E30G 78 E6P-E30G 74 E6S-E30G 182 E6T-E30G 92 E6W-E30G148 E6Y-E30G 33 E6V-E30G 69

TABLE 23 Effect of the combination of amino acid substitution E30G withsubstitutions of amino acid at position 32 of the pro region on theproduction of mature protease of SEQ ID NO: 17 Mutation (Substitution)at Percent activity relative to activity from the positions in proregion modified precursor E30G-A32 E30G (control) 100 E30G-A32R 188E30G-A32N 94 E30G-A32D 69 E30G-A32C 38 E30G-A32Q 133 E30G-A32E 109E30G-A32G 105 E30G-A32H 115 E30G-A32I 150 E30G-A32L 38 E30G-A32K 189E30G-A32P 69 E30G-A32S 122 E30G-A32T 116 E30G-A32W 161 E30G-A32Y 13E30G-A32V 110(c) Site-Saturation Mutagenesis: Generation of Combinations of ThreeSubstitutions in the Pro Region.

The plasmid expressing the combination of to substitutions E6G-E30G inthe pro region comprised in the full-length protease of SEQ ID NO:63 wassubjected to another round of site-saturation mutagenesis of the codonat position 32 to create a library of polynucleotides that encode afull-length protease containing a substitution of amino acid 32 incombination with the E6G-E30G combination of substitutions in the proregion of the protease. The mutation at position 32 was created usingthe QuikChange® site-directed mutagenesis kit (QC; Stratagene) accordingto the directions provided by the manufacturer using forward and reverseprimers of SEQ ID NOS:34 and 35, respectively.

The QC reaction, amplification of the plasmid DNA, and transformation ofE. coli cells were performed as described in Example 1(a). Thesubsequent transformation of Bacillus subtilis competent cells was alsoperformed as described in Example 1(b). Supernatants from Bacilluscultures expressing proteases from modified or unmodified precursor wereanalyzed for protease activity using the AAPF assay as described inExample 1(c).

Results shown in Table 24 show that a triple substitution of amino acidsat positions 6, 30 and 32 further enhance the production of the matureprotease when processed from a pro region containing the twosubstitutions at positions 6 and 30. In particular, the A32E, A32S,A32T, and A32W when in combination with the E6G-E30G double substitutionincrease the production of the mature protease (SEQ ID NO:17) by about73%, 3%, 33%, and 23%, respectively, relative to the level produced bythe doubly mutated precursor comprising the E6G-E30G combination ofsubstitutions. Considering that the E6G-E30G combination produces about80% more mature than the single E30G substitution alone, the triplemutations E6G-E30G-A32E, E6G-E30G-A32S, E6G-E30G-A32T, and E6G-E30G-A32Wcan be calculated to produce 311%, 185%, 239% and 221%, respectively, ofthe level processed from the pro region containing the single E30Gsubstitution.

TABLE 24 Effect of the combination of amino acid substitution E6G-E30Gwith substitution of amino acid at position 32 of the pro region on theproduction of mature protease of SEQ ID NO: 17 Percent activity Mutation(substitution) at E6G-E30G-A32X relative to activity positions in proregion from the modified precursor E6G-E30G E6G-E30G (control) 100E6G-E30G-A32R 47 E6G-E30G-A32N 34 E6G-E30G-A32D 72 E6G-E30G-A32C 43E6G-E30G-A32Q 87 E6G-E30G-A32E 173 E6G-E30G-A32G 58 E6G-E30G-A32H 88E6G-E30G-A32I 21 E6G-E30G-A32L 34 E6G-E30G-A32K 69 E6G-E30G-A32M 88E6G-E30G-A32F 90 E6G-E30G-A32P 100 E6G-E30G-A32S 102 E6G-E30G-A32T 133E6G-E30G-A32W 123 E6G-E30G-A32Y 42 E6G-E30G-A32V 50(d) Effect of Amino Acid Substitution(s) in the Pro Region of thePrecursor Protease on the Production of the Mature Protease of SEQ IDNO:17 in Shake Flask Cultures.

To test the effect of amino acid substitutions in the pro region on theproduction of the mature protease of SEQ ID NO:17 in shake flaskcultures, several of the Bacillus subtilis strains grown in themicrotiter plates as described above and containing a substitution atposition 30 in combination with a second substitution at position 6 or32, and strains containing the combination of three substitutions in thepro region were grown for 48 hours as described in Example 1(e).Supernatant from the shake flask cultures was assayed for AAPF activityas described in Example 1(c).

The results for the activity in strains comprising the combination oftwo E6-E30G or E30G-A32, and three amino acid substitutionsE6G-E30G-A32X are shown in Tables 25, 26 and 27, respectively. Theresults show that the enhancement of protease production obtained frommodified precursor proteases in microtiter cultures is mimicked in shakeflask cultures.

TABLE 25 Effect of the combination of amino acid substitution E30G withsubstitutions of amino acid at position 6 of the pro region of themature protease of SEQ ID NO: 17 in shake flask cultures Mutation(substitution) at Percent activity relative to activity positions in proregion of the modified precursor E30G E6-E30G (control) 100 E6A-E30G 115E6R-E30G 131 E6C-E30G 91 E6G-E30G 142 E6H-E30G 150 E6K-E30G 81 E6S-E30G111 E6W-E30G 145

TABLE 26 Effect of the combination of amino acid substitution E30G withsubstitutions of amino acid at position 32 of the pro region of themature protease of SEQ ID NO: 17 in shake flask cultures Mutation(substitution) at Percent activity relative to activity positions in proregion of the modified precursor E30G E30G-A32 (control) 100 E30G-A32101 E30G-A32 121 E30G-A32 157 E30G-A32 165 E30G-A32 158 E30G-A32 108

TABLE 27 Effect of the combination of amino acid substitution E6G-E30Gwith substitutions at position 32 of the pro region of the matureprotease of SEQ ID NO: 17 in shake flask cultures Percent proteaseactivity relative to Mutation (substitution) at positions activity fromthe modified precursor in pro region E6G-E30G E6G-E30G-A32 (controlprecursor) 100 E6G-E30G-A32E 142 E6G-E30G-A32P 76 E6G-E30G-A32S 98E6G-E30G-A32T 106 E6G-E30G-A32W 135

EXAMPLE 5 The Effect of Mutations in the Pro Region of SEQ ID NO:7 onthe Production of the Mature Alkaline Protease of SEQ ID NO:21

(a) Site-Saturation Mutagenesis of Amino Acids at Positions 6, 30 or 32of the Pro Region

Site-saturation mutagenesis of the pro region on the production of themature protease of SEQ ID NO:21 was performed using the QuikChange®site-directed mutagenesis kit (QC; Stratagene) according to thedirections of the manufacturer. A DNA cassette comprising the AprEpromoter, and the polynucleotide that encodes the full-length proteaseof SEQ ID NO:21 was cloned into the EcoRI and HindIII restriction sitesof the pBN3 vector (Babe et al., Appl. Biochem. 27: 117-124 [1998]).pBN3 (FIG. 4B) to generate the pBN3-P21 plasmid. The P21 DNA cassettecomprised the B. subtilis aprE promotergaattcctccattttcttctgctatcaaaataacagactcgtgattttccaaacgagctttcaaaaaagcctctgccccttgcaaatcggatgcctgtctataaaattcccgatattggttaaacagcggcgcaatggcggccgcatctgatgtctttgcttggcgaatgttcatcttatttcttcctccctctcaataattUttcattctatccatttctgtaaagtttatttttcagaatacttttatcatcatgctttgaaaaaatatcacgataatatccattgttctcacggaagcacacgcaggtcatttgaacgaattUttcgacaggaatttgccgggactcaggagcatttaacctaaaaaagcatgacatttcagcataatgaacatttactcatgtctattttcgttcttttctgtatgaaaatagttatttcgagtctctacggaaatagcgagagatgatatacctaaatagagataaaatcatctcaaaaaaatgggtctactaaaatattattccatctattacaataaattcacagaatagtatttaagtaagtctactctgaatttttttaaaaggagagggtaaaga (SEQID NO:1),

the polynucleotide sequencegtgagaagcaaaaaattgtggatcagcttgttgtttgcgttaacgttaatctttacgatggcgttcagcaacatgtctgcgcaggct(SEQ ID NO:2), which encodes the AprE signal peptideVRSKKLWISLLFALTLIFTMAFSNMSAQA (SEQ ID NO:3), the polynucleotide sequencegctgaagaagcaaaagaaaaatatttaattggctttaatgagcaggaagctgtcagtgagtttgtagaacaagtagaggcaaatgacgaggtcgccattctctctgaggaagaggaagtcgaaattgaattgcttcatgaatttgaaacgattcctgttttatccgttgagttaagcccagaagatgtggacgcgcttgaactcgatccagcgatttcttatattgaagaggatgcagaagtaacgacaatg(SEQ ID NO:6), which encodes the unmodified pro regionAEEAKEKYLIGFNEQEAVSEFVEQVEANDEVAILSEEEEVEIELLHEFETIPVLSVELSPEDVDALELDPAISYIEEDAEVTTM (SEQ ID NO:7), and the polynucleotide sequenceGCGCAATCAGTGCCATGGGGAATTAGCCGTGTGCAAGCCCCAGCTGCCCATAACCGTGGATTGACAGGTTCTGGTGTAAAAGTTGCTGTCCTCGATACAGGTATTTCCACTCATCCAGACTTAAATATTCGTGGTGGCGCTAGCTTTGTACCAGGGGAACCATCCACTCAAGATGGGAATGGGCATGGCACGCATGTGGCCGGGACGATTGCTGCTTTAGACAATTCGATTGGCGTTCTTGGCGTAGCGCCGAGAGCGGAACTATACGCTGTTAAAGTATTAGGGGCGAGCGGTTCAGGTTCGGTCAGCTCGATTGCCCAAGGATTGGAATGGGCAGGGAACAATCGTATGCACGTTGCTAATTTGAGTTTAGGACTGCAGGCACCAAGTGCCACACTTGAGCAAGCTGTTAATAGCGCGACTTCTAGAGGCGTTCTTGTTGTAGCGGCATCTGGAAATTCAGGTGCAGGCTCAATCAGCTATCCGGCCCGTTATGCGAACGCAATGGCAGTCGGAGCTACTGACCAAAACAACAACCGCGCCAGCTTTTCACAGTATGGCGCAGGGCTTGACATTGTCGCACCAGGTGTAAACGTGCAGAGCACATACCCAGGTTCAACGTATGCCAGCTTAAACGGTACATCGATGGCTACTCCTCATGTTGCAGGTGCAGCAGCCCTTGTTAAACAAAAGAACCCATCTTGGTCCAATGTACAAATCCGCAATCATCTAAAGAATACGGCAACGAGCTTAGGAAGCACGAACTTGTATGGAAGCGGACTTGTCAATGCAGAAGCTGCAACTCGT (SEQ ID NO:20),which encodes the mature region of protease 21 (P21).AQSVPWGISRVQAPAAHNRGLTGSGVKVAVLDTGISTHPDLNIRGGASFVPGEPSTQDGNGHGTHVAGTIAALDNSIGVLGVAPRAELYAVKVLGASGSGSVSSIAQGLEWAGNNRMHVANLSLGLQAPSATLEQAVNSATSRGVLVVAASGNSGAGSISYPARYANAMAVGATDQNNNRASFSQYGAGLDIVAPGVNVQSTYPGSTYASLNGTSMATPHVAGAAALVKQKNPSWSNVQIRNHLKNTATSLGSTNLYGSGLVNAEAATR (SEQ ID NO:21).

Each of the 3 codons in the pro region of SEQ ID NO:7, exemplified byNNG/C, comprised in the full-length protease of SEQ ID NO:65, weremutated to be substituted by the 32 possible nucleotide triplets thatencode the 20 naturally occurring amino acids to generate threelibraries as follows. An aliquot of plasmid pJH-P21 DNA comprising thesequence encoding the full-length protease was mutated to generate afirst library of clones encoding all possible substitutions of glutamicacid (E) at position 6 (E6X) of the pro region (SEQ ID NO:7); a secondaliquot was mutated to generate a second library of clones encoding allpossible substitutions of glutamic acid (E) at position 30 (E30X) of thepro region (SEQ ID NO:7); and a third aliquot was mutated to generate athird library of clones encoding all possible substitutions of arginine(A) at position 32 (A32X) of the pro region (SEQ ID NO:7). Complementaryoverlapping primers were designed for mutating the codons of interestwith about 18 bases flanking the NNS codon. The polynucleotide sequencesof the forward and reverse primers used to mutate the amino acids atpositions 6, 30 and 32 are given in Table 1.

The QC reaction, amplification of the plasmid DNA, and transformation ofE. coli cells were performed as described in Example 1(a). Thesubsequent transformation of Bacillus subtilis competent cells was alsoperformed as described in Example 1(b). Supernatants from Bacilluscultures expressing proteases from modified or unmodified precursor wereanalyzed for protease activity using the AAPF assay as described inExample 1(c).

The results given in Tables 28, 29, and 30 showed that all but one ofthe amino acid substitutions of amino acids at positions 6 of the proregion of the precursor protease lead to an enhanced production of themature form of the protease of SEQ ID NO:21, whereas all but one of theamino acid substitutions at positions 30 or 32 showed similar ordiminished protease production when compared to the production of themature protease when processed from an unmodified pro region. Inaddition, site saturation of each of the substituted amino acids showedthat each amino acid can be substituted by two or more amino acids atthe same position to increase the production of the mature form relativeto that obtained from the precursor protease having unmodified proregion.

TABLE 28 Effect of amino acid substitution at position 6 of the proregion on the production of the mature protease of SEQ ID NO: 21Mutation (Substitution) at Percent activity relative to activityposition in pro region from the unmodified precursor E6 (control) 100E6A 84 E6R 85 E6D 57 E6C 90 E6Q 93 E6G 96 E6H 86 E6I 76 E6L 85 E6K 84E6M 73 E6P 63 E6S 93 E6T 94 E6W 40 E6Y 74 E6V 94

TABLE 29 Effect of amino acid substitution at position 30 of the proregion on the production of the mature protease of SEQ ID NO: 21Mutation (Substitution) at Percent activity relative to activityposition in pro region from the unmodified precursor E30 (control) 100E30A 110 E30R 102 E30N 129 E30D 115 E30C 108 E30Q 87 E30G 130 E30H 123E30I 47 E30L 83 E30M 129 E30F 116 E30P 50 E30S 134 E30T 94 E30W 125 E30V74

TABLE 30 Effect of amino acid substitution at position 32 of the proregion on the production of the mature protease of SEQ ID NO: 21Mutation (Substitution) at Percent activity relative to activitypositions in pro region from the unmodified precursor A32 (unmodifiedpro; control) 100 A32R 95 A32N 70 A32D 63 A32C 85 A32Q 67 A32G 70 A32H76 A32L 116 A32M 97 A32F 125 A32P 64 A32S 68 A32T 61 A32V 116Site-Saturation Mutagenesis: Generation of Combinations of Substitutionsin the Pro Region of SEQ ID NO:21.

The plasmid expressing the E30S substitution in the pro region (SEQ IDNO:7) second round of site-saturation mutagenesis of the codon atposition 6 to create a first library of polynucleotides that encode afull-length protease containing a substitution of amino acid 6 incombination with the E30S substitution of the pro region of theprotease. The mutation at position 6 was created using the QuikChange®site-directed mutagenesis kit (QC; Stratagene) according to thedirections provided by the manufacturer using forward and reverseprimers of SEQ ID NOS:26 and 27, respectively (Table 1). Similarly, asecond library of polynucleotides was created to encode a full-lengthprotease containing a substitution of amino acid 32 in combination withthe E30S substitution in the pro region of the protease was created. Thecomplementary overlapping forward primers used to create the library ofmutated polynucleotides comprising the A32X mutation in combination withthe E30S substitution, were the complementary forwardGAGGCAAATGACTCGGTCNNSATTCTCTCTGAGGAAGAG:SEQ ID NO:36, and reverse primerCTCTTCCTCAGAGAGAATSNNGACCGAGTCATTTGCCTC SEQ ID NO:37.

The QC reaction, amplification of the plasmid DNA, and transformation ofE. coli cells were performed as described in Example 1(a). Thesubsequent transformation of Bacillus subtilis competent cells was alsoperformed as described in Example 1(b). Supernatants from Bacilluscultures expressing proteases from modified or unmodified precursor wereanalyzed for protease activity using the AAPF assay as described inExample 1(c).

Results shown in Tables 31 and 32 indicate that most substitutions ofthe amino acid at position 6 (Table 31) of the pro region when incombination with the substitution E30S further enhance the production ofthe mature form of the protease expressed from a polynucleotide encodingan unmodified pro region or a pro region containing the single E30Ssubstitution. Similarly, most substitutions of amino acid at position 32of the pro region when in combination with the substitution E30S at site30, also lead to a further enhancement of production of the mature formof the protease.

TABLE 31 Effect of the combination of amino acid substitution E30S withsubstitutions of amino acid at position 6 of the pro region on theproduction of mature protease of SEQ ID NO: 21 Mutation (Substitution)at Percent activity relative to activity from positions in pro regionthe modified precursor E6-E30S E6-E30S (control, modified) 100 E6A-E30S116 E6N-E30S 64 E6Q-E30S 82 E6G-E30S 119 E6H-E30S 86 E6I-E30S 88E6L-E30S 162 E6K-E30S 107 E6F-E30S 156 E6P-E30S 150 E6S-E30S 99 E6T-E30S74 E6W-E30S 88 E6Y-E30S 162 E6V-E30S 101

TABLE 32 Effect of the combination of amino acid substitution E30S withsubstitutions of amino acid at position 32 of the pro region on theproduction of mature protease of SEQ ID NO: 21 Mutation (substitution)at Percent activity relative to activity from positions in pro regionthe modified precursor E30S-A32 E30S, A32 (control, modified) 100E30S-A32R 113 E30S-A32N 177 E30S-A32D 229 E30S-A32C 112 E30S-A32Q 195E30S-A32E 148 E30S-A32G 194 E30S-A32H 204 E30S-A32L 223 E30S-A32K 180E30S-A32M 181 E30S-A32F 171 E30S-A32P 250 E30S-A32S 205 E30S-A32T 166E30S-A32W 202 E30S-A32Y 116 E30S-A32V 141

We claim:
 1. An isolated modified polynucleotide encoding a modifiedprotease, said isolated modified polynucleotide comprising a firstpolynucleotide encoding a signal peptide, said first polynucleotidebeing operably linked to a second polynucleotide encoding the pro regionset forth in SEQ ID NO:7, wherein said pro region comprises asubstitution selected from the group consisting of: E6A, E6C, E6F, E6L,E6P, E6T, E6W, E6Y, E30A, E301, E30L, E30P, E30T, E30V, E30Y, A32C,A32E, A32G, A32K, A32Q, A32S, and A32T, said second polynucleotide beingoperably linked to a third polynucleotide encoding the mature region ofa protease that is at least 90% identical to the mature protease of SEQID NO: 9, wherein said substitutions enhance the production of saidmature protease by a Bacillus sp. host cell.
 2. The isolated modifiedpolynucleotide of claim 1, wherein said mature protease is a wild-typeor variant alkaline serine protease derived from Bacillus clausii orBacillus lentus.
 3. The isolated polynucleotide of claim 1, wherein saidsignal peptide has an amino acid sequence chosen from SEQ ID NOS:3 and5.
 4. An expression vector comprising the isolated modifiedpolynucleotide of claim
 1. 5. A Bacillus sp. host cell comprising theexpression vector of claim
 4. 6. The host cell of claim 5, wherein saidhost cell is a B. subtilis host cell.
 7. A method for producing a matureprotease in a Bacillus sp. host cell, said method comprising: a)providing the expression vector of claim 4; b) transforming a Bacillussp. host cell with said expression vector; and c) culturing said hostcell under suitable conditions such that said protease is produced bysaid host cell.
 8. The method of claim 7, wherein said Bacillus sp. hostcell is a Bacillus subtilis host cell.
 9. The method of claim 7, whereinsaid mature protease is a wild-type Bacillus clausii or a Bacilluslentus alkaline serine protease, variant or homolog thereof.
 10. Themethod of claim 7, wherein said signal peptide has the amino acidsequence of SEQ ID NO:3, wherein said pro region comprises asubstitution chosen from E6A, E6C, E6F, E6P, E6T, E6W, A32K, and A32T,and wherein said mature protease comprises SEQ ID NO:9.
 11. The methodof claim 7, wherein said signal peptide has the amino acid sequence ofSEQ ID NO:3, wherein said pro region comprises a substitution of anamino acid chosen from E6A, E6C, E6Y, E30A, E30L, E30P, E30T, E30Y,E30V, A32C, A32E, A32G, A32K, and, and wherein said mature proteasecomprises SEQ ID NO:17.
 12. The method of claim 7, wherein said signalpeptide has the amino acid sequence of SEQ ID NO:3, wherein said proregion comprises a substitution of an amino acid chosen from E6A, E30A,E30L, E30T and E30V, and wherein said mature protease comprises SEQ IDNO:19.
 13. The method of claim 7, wherein said signal peptide has theamino acid sequence of SEQ ID NO:3, wherein said pro region comprises anE30A substitution, and wherein said mature protease comprises SEQ IDNO:21.
 14. The isolated polynucleotide of claim 1, wherein said firstpolynucleotide encodes the signal peptide of SEQ ID NO:3, wherein saidpro region comprises a substitution of an amino acid chosen from E6A,E6C, E6Y, E30A, E30L, E30P, E30T, E30Y, E30V, A32C, A32E, A32G, A32K,and A32T, and wherein said mature protease comprises SEQ ID NO:17. 15.The isolated polynucleotide of claim 1, wherein said firstpolynucleotide encodes the signal peptide of SEQ ID NO:3, wherein saidpro region comprises a substitution of an amino acid chosen from E6A,E6C, E6F, E6P, E6T, E6W, A32K, and A32T, and wherein said matureprotease comprises SEQ ID NO:9.
 16. The isolated polynucleotide of claim1, wherein said first polynucleotide encodes the signal peptide of SEQID NO:3, wherein said pro region comprises a substitution of an aminoacid chosen from E6A, E30A, E30L, E30T and E30V, and wherein said matureprotease comprises SEQ ID NO:19.
 17. The isolated polynucleotide ofclaim 1, wherein said first polynucleotide encodes the signal peptide ofSEQ ID NO:3, wherein said pro region comprises a substitution of anamino acid chosen from E6A, E6L, E6F, E6T, E301, E30L, E30P, E30T, E30Y,E30V, A32Q, A32S and A32T, and wherein said mature protease comprisesSEQ ID NO:11.
 18. The isolated polynucleotide of claim 1, wherein saidfirst polynucleotide encodes the signal peptide of SEQ ID NO:3, whereinsaid pro region comprises the amino acid substitution E30A, and whereinsaid mature protease comprises SEQ ID NO:21.
 19. The method of claim 7,wherein said signal peptide has the amino acid sequence of SEQ ID NO:3,wherein said pro region comprises a substitution of an amino acid chosenfrom E6A, E6L, E6F, E6T, E301, E30L, E30P, E30T, E30Y, E30V, A32Q, A325and A32T, and wherein said mature protease comprises SEQ ID NO:11.